Buffer solutions containing Na2CO3 and NaHCO3 range in pH from 10.0 to 11.0. The chemical equation below represents the equilibrium between CO32−and H2O, and the table lists the composition of four different buffer solutions at 25°C.
Which of the following chemical equilibrium equations best shows what happens in the buffer solutions to minimize the change in pH when a small amount of a strong base is added?
answer choices
H3O+(aq) + OH−(aq) ⇄ 2 H2O(l)
HCO3−(aq)+ OH−(aq) ⇄ CO32−(aq) + H2O(l)
CO32−(aq) + H3O+(aq) ⇄ HCO3−(aq) +H2O(l)
CO32−(aq) + H2O(l) ⇄ HCO3−(aq)+ OH−(aq)
B. HCO3−(aq)+OH−(aq)⇄CO32−(aq)+H2O(l). Buffer solutions containing Na2CO3 and NaHCO3 range in pH from 10.0 to 11.0. The chemical equation below represents the equilibrium between.
CO32−and H2O, and the table lists the composition of four different buffer solutions at 25°C. A chemical equation is made up of reactants, products, and an arrow indicating the direction of the reaction. A balanced chemical equation is one in which the number of atoms in all molecules is equal on both sides of the equation. The law of conservation of mass is not applicable in the preceding case. A chemical equation is a graphical description of a chemical process using symbols and chemical formulae. The reactant entities are on the left, and the product entities are on the right, with a plus sign between the entities in both the reactants and the products, and an arrow pointing towards the products to indicate the reaction's direction. Chemical formulae might be symbolic, structural (pictorial), or both.
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Chlorine has two principal stable isotopes, 35Ci (isotopic mass 34.9689) and PCI (isotopic mas 36.9659). The atomic mass of Cl is 35.4527 amu. Which of the following options correctly describe these isotopes? Check all that apply. O The more abundant isotope comprises 75.774% of all stable Cl atoms O Ci comprises 34.97% of all stable Cl atoms O Ci has the greater abundance. O The two isotopes are equally abundant.
The more abundant isotope comprises 75.774% of all stable Cl atoms.
What is an isotope?
Isotopes are two or more types of atoms (or nuclides is the technical term) that have the same atomic number (the number of protons in their nuclei) and position in the periodic table (and therefore belong to the same chemical element) and that are different. in nucleon numbers (mass numbers) due to the different number of neutrons in their nuclei. While all isotopes of a given element have nearly the same chemical properties, they have different atomic masses and physical propertiesTo know more about isotopes, click the link given below:
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Q: Determine the hardness of water sample prepared by dissolving 1.36 gram of CaCl2 in 500 ml distilled water.
The hardness of water sample prepared by dissolving 1.36 gram of CaCl[tex]_2[/tex] in 500 ml distilled water is 0.00272 gram/ ml.
What is hardness of water?The quantity of dissolved magnesium and calcium in the water is the simplest way to define water hardness. Calcium and magnesium are the main dissolved minerals in hard water. The last time someone washed your hands, you could have really felt the impacts of hard water.
"Soap " is created in hard water when soap interacts with the water's comparatively high calcium content. More soap and detergent is required to be get things clean while using hard water, whether it's your hands, your hair, or your clothes.
hardness of CaCl[tex]_2[/tex]=mass of CaCl[tex]_2[/tex]/ volume of distilled water
= 1.36 gram÷500 ml
=0.00272 gram/ ml
Therefore, the hardness of water sample prepared by dissolving 1.36 gram of CaCl[tex]_2[/tex] in 500 ml distilled water is 0.00272 gram/ ml.
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Imagine a small synthetic vesicle made from pure phospholipids enclosing an interior lumen containing 1 mM glucose and 1 mM sodium chloride. If the vesicle is placed in pure water, which of the following happens faster?a. water diffuses inb. sodium chloride diffuses outc. glucose diffuses out
The small synthetic vesicle made from pure phospholipids enclosing interior lumen containing 1 mM of glucose and 1 mM of sodium chloride. If it is placed in pure water , water diffuses in.
The osmosis is the process in which the solvents move from the low concentration to the high concentration through the semi- permeable membrane. The three types of osmosis is given as :
1) Hypotonic
2) Hypertonic
3) Isotonic
The water and the solvents tries to move into the low concentration to the high concentration through the semi- permeable membrane.
Thus, water diffuses in when synthetic vesicle made from pure phospholipids enclosing interior lumen containing 1 mM of glucose and 1 mM of sodium chloride and it is placed in pure water.
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which of the followning equations best represents the reacting species in the reactio between zn metal and nicl2
Undoubtedly, the described reaction is a redox one.Redox reactions are defined as those that include a change in oxidation number, including both an increase and a drop in number.
Is Zn cl2 --> zncl2 a redox reaction?The described reaction is unquestionably a redox one.Redox reactions are those that include an alteration in the quantity of oxidations present, including both an increase and a decrease.If this doesn't happen, the response is non-redox.One of the numerous forms of redox reactions is the decomposition process. Blended Reaction.Removal Reaction.The reduction of the sulfur is brought about by the zinc, which gains electrons.Thus, the term "reducing agent" refers to zinc.Anode-based oxidation always entails the loss of electrons.Considering that oxidation is taking place in the Zn2+(aq)/Zn(s) half cell, zinc is the logical anode.The electrode's Zn atoms lose two electrons and become Zn2+, which is then present in the solution (aq).To learn more about Redox reactions refer
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in order for one type of atom to substitute for another in a solid solution, the substituting atom must be: (select all that apply.) identical in size similar in size the same element from the same group from the same period
"An atom must be similar in size" in order for one type of atom to substitute for another in a solid solution.
What properties must atoms share in order for them to substitute for one another?Atoms are called the basic building blocks of all matter. An element seems to be a substance that consist only one type of atom. Each element has their own name and distinct properties that set it apart from the others.The two atoms' sizes must be comparable. Otherwise, one atom cannot easily take the place of the other atom. The crystal structure of the two atoms must be the same. It would be difficult for one atom to substitute for the other if the two atoms crystallized in different ways.A substitution reaction occurs when one atom or group of a substance is replaced by another atom or group.The complete question:
"Select all that apply.
The requirements for one type of atom to substitute for another in a solid solution are:
All substitutions must be limited to the same element.
An atom must be identical in size.
An atom must be similar in size.
The substituting atom must be from the same period.
The substituting atom must be from the same group."
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Which of the statements about mole ratios are true? Select all that apply.
A. Mole ratios include coefficients from a balanced chemical equation.
B.
Mole ratios do not include stoichiometric coefficients.
C. Mole ratios can only be formed between two products.
D. Mole ratios can only be formed between two reactants.
E. Mole ratios can be formed between any combination of reactants and/or products.
F. Mole ratios always have reactants in the numerator and products in the denominator.
A and E are statements that can be considered to be true for mole ratio.
A. The amount of any two materials in moles in a chemical process is related by a ratio factor called a mole ratio. The claim that Mole ratios incorporate coefficients from a balanced chemical equation is hence true.
B. The number in front of atoms, ions, and molecules in a chemical process is the stoichiometric coefficient. Therefore, the claim that stoichiometric coefficients are not included in Mole ratios is incorrect.
C. It is possible for mole ratios to arise between two products or reactants. As a result, statement C is false.
D. It is untrue that mole ratios may only be created between two reactants, as stated in statement D.
E. The ratio of the moles of any two chemicals present in a reaction is known as the mole ratio. Consequently, it is accurate to say that Mole ratios can develop between any group of reactants and/or products.
F. There is a switchable numerator and denominator. The assumption that reactants are always in the numerator and products are always in the denominator of Mole ratios is thus false.
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The statements above here A and E are true and B,C,D and F are false in the given statements
A. Coefficients from an equilibrium chemical equation are included in mol ratios. This is true so because coefficients in a chemical equation denote the molar mass of each reactants and the products, and a molecular formula does have the same quantity of atoms of the elements on the both sides of this argument.
E. Mole proportions can be created between any set of products or reactants. This is accurate since a mole ratio is only a comparison of how much each component contributes to a chemical process.
The claims B, C, D, & F are false:
B. Stoichiometric coefficients are not included in mole ratios.
C. Only between two products can mole ratios be generated.
D. above, mole ratios can form between any combined effect of reactants and/or products. Only between two reactants may mol ratios be created.
F. above, mole ratios can form between any combined effect of reactants and/or products.
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question 3 is unpinned. click to pin. question at position 3 when 1,2-dibromo-1-phenylethane is heated with sodium hydroxide, a compound with the ir spectrum provided is produced. propose a structure for this product.
Proposed Structure is CH3CHBrCH2Br + NaOH → CH3CH(OH)CH2Br
Heating of 1,2-dibromo-1-phenylethane and NAOHWhen the sodium hydroxide is heated, 1,2-dibromo-1-phenylethane undergoes a nucleophilic substitution process to produce 1-phenylethyl sodium bromide. Sodium bromide and 1-phenylethane are the results of the process, and they are both isolable. An S N 1 mechanism, involving the creation of a carbocation intermediate, underlies the reaction. The intermediate is attacked by the nucleophile, in this case sodium hydroxide, who then produces the end result. In order to turn alkyl halides into alkanes, this reaction is frequently utilized. Additionally serving as a base in the process, sodium hydroxide aids in deprotonating the alkyl halide, which permits the reaction to proceed.
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The density of hexane is 0.66g/ml and the density of water is 1.00gml. A 1.0 g sample of i2 is added to the mixture which is shaken again. Which of the following best predicts happens to the i2?
The i2 will settle to the bottom of the mixture,of the following best predicts happens to the i2.
What is the mixture?
The mixture is a combination of ingredients that are blended together to create a unique and distinct product. It can be anything from a cake batter to a marinade, a salad dressing to a bread dough. Mixtures often include multiple components that work together to produce the desired outcome. Plagiarism-free mixtures are created when each ingredient is carefully selected and all sources are properly cited. By using original ingredients, a mixture can be created that is both unique and delicious.
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2K3N + 3CaCl2 → 6KCl + Ca3N2
1 mol K3N = 131.301 g K3N
1 mol CaCl2 = 110.984 g CaCl2
1 mol KCl = 74.551 g KCl
1 mol Ca3N2 = 148.248 g Ca3N2
How many grams of CaCl2 would it take to make 1.5 moles of KCl?
a
54.213 g
b
83.238 g
c
166.476 g
d
110.984 g
To solve this we must be knowing each and every concept related to mole and and its calculations. Therefore, 83.17g is the grams of CaCl[tex]_2[/tex] would it take to make 1.5 moles of KCl. The correct option is option B.
What is mole?A mole is merely a measuring unit. In reality, it is one of International System of Units' seven foundation units (SI). When basically determines are insufficient, new units are created.
Chemical reactions frequently occur at levels that use grams would be inappropriate, but using actual figures of atoms/molecules/ions would also be misleading.
It's much easier to write' mole' than '6.02x10²³' whenever you wish to refer to a huge number of things. That is essentially why and how this particular component was created.
2K[tex]_3[/tex]N + 3CaCl[tex]_2[/tex] → 6KCl + Ca[tex]_3[/tex]N[tex]_2[/tex]
mole ratio between CaCl[tex]_2[/tex] and KCl is 1:2
2 mole of KCl requires 1 mole of CaCl[tex]_2[/tex]
1 mole of KCl requires 1/2 moles of CaCl[tex]_2[/tex]
1.5 moles of KCl requires (1/2)×1.5= 0.75 moles of CaCl[tex]_2[/tex]
mass of CaCl[tex]_2[/tex] = 0.75 moles ×110.9g/mol
= 83.17g
Therefore, 83.17g is the grams of CaCl[tex]_2[/tex] would it take to make 1.5 moles of KCl.
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orrectly arrange the steps in order for calculating the molecular mass of H,SO4. Place the first step at the top of the list. t Place these in the proper order. .008 amu) + (32.07 amu)+ (4 x 16.00 amu). The molecular mass of H2SO (2 x1 The molecular mass of H2SO4 98.09 amu. The molecular mass of H,so,-(2 x the atomic mass of H) + (the atomic mass of S) (4 x the atomic mass of o
The result of the molecular mass is 98.08 amu
What are the correct arrangement step in order for calculating the molecular mass?The molecular mass is the sum of the atomic masses of all the atoms in a molecule.It is typically measured in atomic mass units (amu) or daltons (Da).It can be calculated by adding together the atomic masses of each element present in the molecule.It is useful for characterizing and identifying different molecules.It can be used to determine the molar mass, which is used in stoichiometry calculations.And the steps are:Determine the atomic mass of H, S, and O.Multiply the atomic mass of O by 4.Add the atomic mass of S to the result from step 2.Multiply the atomic mass of H by 2.Add the atomic mass of H from step 4 to the result from step 3.The final result is the molecular mass of H2SO4, which is 98.09 amu.To learn more about molecular mass refer:
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What should you do if a fire starts in a beaker? question 18 options: O pour water on the fire. O wait and see if the fire goes out on its own. O cover the fire with a rag. O cover the mouth of the beaker with a watch glass.
If a fire starts in a beaker, the best option among the options provided to extinguish the fire is to cover the mouth of the beaker with a watch glass, hence the correct answer is the last option given.
For safety precautions and methods to be taken in a laboratory during any experiment or research is very important. Hence there are several ways safety hazards can be prevented or stopped.
For major fire hazards, security must be called to put out the fire in all scenarios. While for minor fires as like fire in a beaker, the hazard can be overcome by several easy cautious steps.
If we pour water in the beaker to stop the fire, that may cause the fire to be enhanced rather to be dissuaded, as if in presence of a reactive fuel, like magnesium (which could have been the cause of fire), the oxygen present in the water can cause combustion thus increasing the hazard. Hence first option is ruled out.
If we wait for the fire to go out on it's own, there are chances that the fire may come in contact with any inflammable item nearby which can enhance the fire further adding to the problem. Thus, this option is ruled out too.
Covering the fire with a rug is also not an efficient way to put out a fire in a beaker as a rug generally is very inflammable, and hence it would catch on fire easily, causing more difficult situations rather than a solution.
If we cover the mouth of the beaker with a watch glass, the fire would eventually go out as all the oxygen present in the beaker gets used for combustion. Covering the mouth of the beaker prevents any oxygen from outside to enter inside the beaker. Thus, this is a better option for the solution to the situation. Thus the answer to the question is the last option.
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which of the following processes can be accompanied by carbocation rearrangements? neither ozonolysis nor alkylation of an alkyne only alkylation of an alkyne both ozonolysis and alkylation of an alkyne only ozonolysis
Both ozonolysis and alkylation of an alkyne only ozonolysis processes can be accompanied by carbocation.
How do you explain the carbocation?A molecule called a carbocation has three bonds and a positively charged carbon atom. They are essentially carbon cations, to put it simply. It was once referred to as carbonium ion. Any even-electron cation with a sizable positive charge on the carbon atom is now referred to as a carbocation.An ion having a carbon atom that is positively charged is called a carbocation. The methenium CH⁺ ₃, methanium CH⁺ ₅ and vinyl C ₂H⁺ ₃ cationsare a few of the more straightforward examples. Carbocations with several positively charged carbon atoms are also occasionally found.All carbon atoms in carbocations, also referred to as carbonium ions, are positively charged. A cation is a positive ion, and the "carbo" part of the term refers to an atom of carbon.Learn more about carbocation refer to :
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Carbonic acid is a buffer that contributes to pH stability in human blood. Write out this chemical equation and explain what happens if our blood increases or decreases in pH
Answer: HCO3- + H3O --> H2CO3 + H2O (If an a strong acid is present)
H2CO3 + OH- --> HCO3- + H2O (If a strong base is present)
Explanation: Thankfully, we have buffers in our blood, without this buffer, one cup of lemon juice contains enough Hydronium ions (H3O) to kill us. This brings us to our first reaction. In this H2CO3/HCO3- buffer system, HCO3- acts as a weak base. If some strong acid that 100% dissociates into H3O+ happens to enter your blood, instead of the pH decreasing significantly it will only decrease slightly as HCO3- eliminates the H3O+ maintaining a relatively equal pH.
On the other hand, we have the H2CO3 reaction, if, for example, you decided to inject yourself with NaOH (Don't do it) it will dissociate 100% into OH. Since H2CO3 is a weak acid it will react with a strong base eliminating the OH- thus maintaining a stable pH.
Hope this helps. and if you need an explanation of why pH goes up slightly please comment. Good luck with Acid/Base/Equilibrium!!
Platelet dense granules are storage organelles for which the following that are released after activation?
a. Calcium, ADP, and serotonin
b. Fibrinogen, glycoprotein Ib, and VWF
c. ADP, thromboxane A2, and FV
d. Lysosomal granules, ATP, and FVIII
Platelet dense granules are storage organelles for which the substances released after activation is ADP, thromboxane A2, and FV.
Blood platelets are incredibly well-organized cells with a variety of organelles. Different sorts of components, some of which are at high concentrations, are stored in three distinct granule populations. Thus, platelets move some particular substances throughout the entire body. In the course of circulation, platelets respond to diverse stimuli and release the substances kept in the particular granules. A crucial stage of initial hemostasis is the "releasing reaction." Mitochondrial energy and the dense tubular system's messengers, which are needed for platelet reactivity, are delivered by these structures. Regarding the composition and function of the released elements, each granule population has unique characteristics. Small non-protein molecules are secreted by dense granules in order to draw in additional platelets. Large sticky and healing proteins are found in alpha-Granules.
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How many grams of CO2 are used when 8.50 g of O2 are produced?
So, in order for a Ceo to make carbon plus oxygen Gus, we must first formulate the mathematical formula for it. What does CO2 therefore equal? 8.5 g oh from there.
How many granules of CO2 are employed to make 6.5 grams of O2?Here, Bye Cyclorama four from 6.5g of 02 twice one mode of 021 per 32g of co, two from one mole of CO2 times 24.1 g of c 02 per one molecule of c 02, and three from one mole for 02 times 6.5g of 02 times 32g of co. As a result, this CO2 mask is equivalent to 8.9 grams of CO2. I'm grateful.
How is CO2 yield determined?The best approximate method to get your carbonated drink production facility's CO2 Yield is to divide the amount of carbonated beverages generated during the investigated time divided by the amount of CO2 that was consumed each month.
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Which of the following affect the amount by which the freezing point of liquid is lowered by the addition of a solute? More than one answer may be correct.
A. Whether or not the compound is ionic.
B. How soluble the solute is in the solvent.
C. The volume of the solvent.
D. The value of the freezing point for the pure solvent.
E. The identity of the chemical species being dissolved.
The options that affect the amount that the freezing point is lowered by the addition of the solute include :
A. Whether or not the compound is ionic.B. How soluble the solute is in the solvent.How can solutes affect the freezing point of liquids ?The increasing of a solvent's boiling point as a result of the addition of a solute is known as boiling point elevation. Similar to freezing point depression, adding a solute lowers the freezing point of a solvent. In actuality, a solvent's freezing point drops as its boiling point rises.
Any solvent's freezing point will be lowered by the presence of a solute; this action is known as freezing-point depression. The fact that the solute is present in the liquid solution but not in the pure solid solvent is crucial to understanding this phenomenon.
This includes the compound being ionic or the solubility of the solvent.
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Which of the following electron configurations is for an inert gas and explain why?
(A) 1s22s22p63s23p6
(B) 1s22s22p63s2
(C) 1s22s22p63s23p64s1
(D) 1s22s22p63s23p63d24s2
(A)1s22p63s23p6 Gases classified as inert are those that do not react with any other substances or elements due to their stability
Inert gases don't participate in the combustion process and don't interact with other substances A room or small area filled with an inert gas will have less oxygen which will slow the fire's ability to burn. In order to prevent water damage inert gases are employed in extinguishing systems in places like rooms containing electrical equipment. Depending on the parameters taken into consideration different categorization schemes for dangerous gases may be considered Here two concepts chemical and toxicological classifications are utilised The nature of the components that make up gases, such as carbon nitrogen, sulphur phosphorus halogen compounds and halogenated compounds, etc is generally used to classify chemicals Chemical categorization of toxins
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(A)1s22p63s23p6 Gases classified as inert are those that do not react with any other substances or elements due to their stability
Inert gases don't participate in the combustion process and don't interact with other substances A room or small area filled with inert gas will have less oxygen which will slow the fire's ability to burn. In order to prevent water damage inert gases are employed in extinguishing systems in places like rooms containing electrical equipment. Depending on the parameters taken into consideration different categorization schemes for dangerous gases may be considered Here two concepts chemical and toxicological classifications are utilized The nature of the components that make up gases, such as carbon-nitrogen, sulfur phosphorus halogen compounds and halogenated compounds, etc is generally used to classify chemicals Chemical categorization of toxins
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check the box next to each molecule on the right that has the shape of the model molecule on the left:
The BrF4- is the box next to each molecule on the right that has the shape of the model molecule on the left.
What is molecule?
A molecule is the smallest particle in a chemical element or compound that possesses the properties of that element or substance. Atoms bound together by chemical bonds form molecules. There are two different kinds of molecules.
What is atom ?
An atom is a specific kind of material particle that makes up a chemical element. The core nucleus of an atom is surrounded by either many negatively charged electrons or a positively charged electron. The positively charged nucleus is made up of two comparatively large particles called protons and neutrons.
Since hybridisation of central atom(Br) is sp3d2 so geometry of molecule is octahedral but Br have 2 lone pair of electron in axial position so shape is square planar.
Therefore, BrF4- is the box next to each molecule on the right that has the shape of the model molecule on the left.
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complete the diagram to show how clouds form when warm, moist air rises and cools
Use the words: evaporation, cooling air, condensation, and particles
When the vaporized water in the air condenses to form visible water droplets or ice crystals, clouds are created. When a parcel of air becomes saturated, it can no longer hold all the water it contains in vapor form and begins to condense into a liquid or solid.
What are clouds?A cloud is a collection of ice or water vapor floating in the atmosphere.
Cloud formation involves the following processes:
evaporation - this is the process where liquid water changes to gas and rises into the atmosphere
condensation - this occurs as a result of cooling air in the atmosphere converting forming visible water droplets or ice crystals on dust particles.
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Write a paragraph about chemical reactions in everyday life, that cause pollution of the environment.
Pollutants of many different forms enter the environment as a result of chemical interactions in daily living. Significant soil pollution has been brought on by mining, agriculture, and waste disposal.
What is chemical pollution?Chemical pollution is the act of contaminating the environment with chemicals that do not occur naturally.
The delicate ecosystems of the Earth's surface can be harmed by chemical pollution. Biodiversity and population food production are both impacted by soil health. Marine biodiversity has also been impacted by high or prolonged chemical exposure
Biodiversity: What is it?The diversity of animals, plants, fungi, and even microbes like bacteria that make up our ecological landscape are all included in what is known as biodiversity.
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if a certain metal is placed in an ionic solution containing another metal an no reaction occurs, then the metal originally in the solution is
a. a halogen
b. higher on the activity series
c. not on the activity series
d. unreactive
b. higher in the activity sequence. If a given metal is introduced in an ionic solution containing another metal and no reaction happens, the metal initially in the solution is returned to the solution.
Ionic solutions are ones that include ions in order to transmit electricity through them. An electrolyte disintegrates into ions when it dissolves in water. Electrolytes that degrade into ions can only conduct electricity when molten or liquid. This type of mole is usually large and is caused by a condition that affects melanocytes, or pigment-producing cells (melanin). Melanocytic nevi might seem rough, flat, or raised. They might be present from birth or develop later in adulthood. Melanocytic nevi can become cancerous in rare circumstances. The majority of cases do not warrant treatment, although The mole must be removed in specific instances. Moles (nevi) are a kind of skin growth that is rather common. Because of clusters of pigment-forming cells, they appear as minute, dark brown spots (melanocytes).
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which of the following options correctly describes how straight-chain alkanes are named? multiple choice question. alkanes are named with the root based on the number of carbon atoms followed by the suffix -ane. alkanes are named with the number of carbon and hydrogen atoms followed by the suffix -ane. alkanes are not named according to the greek prefixes. alkanes are named with the root based on the number of hydrogen atoms followed by the suffix -ane. alkanes are named with the root based on the number of atoms followed by -ide.
The straight-chain alkanes are named with the root based on the number of carbon atoms present in the alkane, followed by the suffix -ane.
Alkanes are types organic compounds, a series of hydrocarbon compounds, that consist of single-bonded carbon and hydrogen atoms. These are known as saturated hydrocarbons. The formula for Alkanes is CnH2n+2, and are subdivided into three groups, namely - chain alkanes, cycloalkanes, and the branched alkanes.
Alkanes are the simplest series or family of hydrocarbons. They contain only carbon and hydrogen in simplest form. Each carbon atom forms four bonds (either with another carbon atom or a hydrogen atom) and each hydrogen atom forms one bond i.e. with a carbon atom.
Straight-chain alkanes or simply chain alkanes are named by using a stem/root that indicates the number of carbon atoms present in the alkane (meth = 1 C, eth = 2 C's, prop = 3 C's, etc.) to which is added the suffix -ane, indicating that the molecule is indeed an alkane (that is, that the carbon atoms are all connected by single bonds).
Thus first option is the answer to the question.
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A solution with 8.35 g of a non-electrolyte solute in 50.0 g naphthalene (Kfp = 6.90°C/m) freezes at 76.5°C. Pure naphthalene freezes at 81.0°C. What is the molar mass of the solute?
A solution with 8.35 g of a non-electrolyte solute in 50.0 g naphthalene (Kfp = 6.90°C/m) freezes at 76.5°C. Pure naphthalene freezes at 81.0°C. The molar mass of the non-electrolyte is 256.134g /mol
What is molar mass ?The term molar mass is defined as the mass in grams of one mole of the compound.
Given:
Naphthalene usually freezes at 81°C
New Freeing Point = 76.5°C
Depression in freezing point
= 81°C - 76.5°C
= 4.5°C
We know depression in freezing point is given by the formula as below;
Kf x m
where m is the molarity
So, 4.5oC = 6.90°C/m x m
m = 0.652m
Molality = moles of solute dissolved per kilogram of solvent
50g of naphthalene is the solvent
50g = 0.05kg
Molality = moles of solute / 0.05
0.652 x 0.05 = moles of solute
Therefore, there are 0.0326 moles of non- electrolyte
0.0326 moles make 8.35g
So, in 1 mole there are 256.134g
Thus,the molar mass of the non-electrolyte is 256.134g /mol.
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Which of the following units are used to measure heat? Select all that apply.
The units used to measure heat are:1 - kilocalories, 3 - joules, 4 - Kelvin, and 6 - calories
Kilocalories and calories are units of energy, often used to express the energy content of foods. Joules is the SI unit of energy, often used to express the amount of heat energy. Kelvin is the SI unit of thermodynamic temperature, often used in scientific and technical applications.
Celsius and Fahrenheit are units of temperature, but not heat. Heat is defined as the energy relocated from one body to another as a consequence of a temperature difference. So temperature is related to heat but it doesn't measure heat.
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The complete question is :
Heat is measured using which of the following units? Select all that apply.
1 - kilocalories
2 - Celsius
3 - joules
4 - Kelvin
5 - Fahrenheit
6 - calories
pH and pOH Formulas
pH = -log[H3O+]
pOH = -log[OH−]
pH + pOH = 14.00
Concentration Formulas
[H3O+] = 10-pH
[OH−] = 10-pOH
[H3O+][OH−] = 1.0 × 10-14
Round your answer to the nearest hundredth
A solution has a hydronium concentration of 4.7 × 10-11. What is the pH of the solution?
The pH of the solution as we can see is 10.3 from the calculations here.
What is the pH of the solution?We can see that the question does open with all the basic facts that we need to help us to solve the question and one of those is the definition that we know that the pH of the solution can be defined as the negative logarithm of the hydronium ion concentration of a solution.
Now we know that;
pH = -log[[tex]H_{3} O^+[/tex]]
Then we have from the question that;
[[tex]H_{3} O^+[/tex]] = 4.7 × 10-11
pH = -log(4.7 × 10-11)
pH = 10.3
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Solutions of Electrolytes are formed from nondissociating molecules that are nonconductors of electricity. An example would be sugar dissolved in water. True or false
A sugar solution in water, on the other hand, is incapable of conducting a current sugar is thus a non-electrolyte. Therefore the given statement is false.
What is an electrolyte?An electrolyte is just a medium containing ions that conducts electricity through the movement of those ions but does not conduct electrons. Most soluble salts, acids, and bases dissolved in a polar solvent, such as water, fall into this category.Because of the presence of free-flowing ions, electrolyte solutions have the potential to conduct electricity. This is because when an ionic solution dissolves in water, the ionic compound is dissociated into ions, which allows for the conduction of electricity.While electrolyte drinks should contain some sugars, which are beneficial for sodium absorption and as an energy source, electrolyte drinks without sugars can accomplish nearly the same thing as long as the concentration of the remaining electrolytes is adjusted accordingly.To learn more electrolyte refer to :
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In all covalent bonds, valence electrons are ___
lost
gained
shared
shared
Explanation:Covalent bonds are characterized by the sharing of valence electrons.
Electronegativity
Covalent bonds occur between atoms that have similar electronegativity. Remember that electronegativity is how strongly an atom pulls electrons toward itself. So, if 2 atoms have similar electronegativities, then they will pull somewhat equally upon the electrons and share them. Most commonly, covalent bonds occur between nonmetals.
Ionic Bond
The second major form of bonding is ionic bonding. Ionic bonds form when there is a large difference in electronegativities. The difference is great enough that one of the atoms will completely lose one or more electrons, while the other will take the electrons. Since electrons are being transferred, the atoms become ions. Ionic bonds commonly occur between metals and nonmetals.
Suppose an iron-58 nuclide transforms into an iron-59 nuclide by absorbing a neutron. Complete the nuclear chemical equation below so that it describes this nuclear reaction. 59 26 Fe
Refer to the attachment.
question at position 9 given a chemical reaction h2 o2 --> h2o. if you start with 4 g h2 and 40 g o2 and let the reaction go to completion, what mass of o2 left
40 g O2 - (4 g H2 x 4 g O2/2 g H2) = 32 g O2
Therefore, 32 g O2 mass is left after the reaction goes to completion.
What is mass?
Mass is a measure of the amount of matter in a given object. It is measured in kilograms (kg) or grams (g). Mass is related to weight, which is a measure of the force of gravity on an object. An object's mass remains the same regardless of its location, while its weight will vary depending on the strength of the gravitational pull in that location. Mass is an important concept in physics, as it is used to calculate many physical characteristics, such as force, acceleration, and energy.
Therefore, 32 g O2 mass is left after the reaction goes to completion.
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