The most likely the mass of the dust formed on the burning the piece of paper is 2.5 grams.
According to the law of conservation of mass : The mass can neither be created nor be destroyed but it will only be transformed from the one form to the another. In the chemical reaction the total mass on the reactant side will always be equal to the total mass of the product side.
The mass on the reactant side:
The Mass of the paper = 4.8 grams
On the product side:
Mass of the ash = 0.1 g
Mass of the smoke = 2.2 g
Total mass = 4.8 g
Mass of the Dust = 4.8 - ( 2.2 + 0.1)
= 2.5 g
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This question is incomplete, the complete question is :
One student burned a piece of paper weighing 4.8 grams. The table below shows the mass of the materials formed by burning the paper.
Ash- 0.1 grams
Smoke- 2.2 grams
Dust- ?
Which is most likely the mass of the dust formed on the burning piece of paper?
A. 2.2 grams
B. 2.3 grams
C. 2.5 grams
D. 2.6 grams
If an atom/ion has 3 protons, 4 neutrons and 4 electrons, is it a neutral atom or an ion? If it is an ion what is its charge?
The ion is a lithium ion with a charge of -1, often written as Li-.
What is an ion?
An ion is an atom or molecule that has a non-zero net electrical charge due to the loss or gain of one or more electrons. Ions can be positively charged (cations), when they lose electrons, or negatively charged (anions), when they gain electrons.
The number of protons in an atom/ion determines its atomic number and its identity.
In this case, the number of protons is 3, which corresponds to the element lithium (Li) in its neutral state. However, the number of electrons is 4, which means that this is an ion of lithium.
To determine the charge of the ion, we need to compare the number of protons (positive charges) to the number of electrons (negative charges). In this case, there are 3 protons (3+) and 4 electrons (4-), so the ion has a charge of -1.
Therefore, the ion is a lithium ion with a charge of -1, often written as Li-.
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What are the four main types of chemical reactions?
Answer:
synthesis, decomposition redox
Explanation:
Answer:
The four main types of chemical reactions are synthesis, decomposition, exchange (single replacement), and reduction-oxidation (redox).
Explanation:
what is the best description of a secondary active transport process that cotransports an amino acid with na ?
A secondary active transport process that cotransports an amino acid with Na+ is an example of a symport mechanism, in which both molecules move in the same direction across the cell membrane.
A secondary active transport process that cotransports an amino acid with Na+ is an example of a symport mechanism, in which both molecules move in the same direction across the cell membrane. Specifically, this type of transport involves the coupling of the energy stored in the electrochemical gradient of Na+ to the uphill transport of an amino acid against its concentration gradient. As Na+ flows down its concentration gradient into the cell, it drives the movement of the amino acid into the cell as well. This type of transport is known as secondary because it indirectly uses energy stored in the electrochemical gradient of Na+ to drive the movement of the amino acid, rather than directly using ATP hydrolysis like primary active transport mechanisms.
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the molecular weight of hemoglobin is about 65,000 g/mol. hemoglobin contains 0.35% fe by mass. how many iron atoms are in a hemoglobin molecule?
there are approximately 4.069 x [tex]10^{23}[/tex] iron atoms in a hemoglobin molecule.
The number of iron atoms in a hemoglobin molecule can be calculated as follows:
First, determine the mass of iron in a single hemoglobin molecule:
mass of iron = 0.35% * 65,000 g/mol = 227.5 g/mol
Next, convert the mass of iron to the number of iron atoms by dividing by the atomic mass of iron:
1 iron atom = 55.845 g/mol
number of iron atoms = 227.5 g/mol / 55.845 g/mol/atom = 4.069 x [tex]10^{23}[/tex]iron atoms/mol
So there are approximately 4.069 x [tex]10^{23}[/tex] iron atoms in a single hemoglobin molecule.
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percy julian was a synthetic organic chemist that successfully synthesized physostigmine. true/false
Percy Julian was a synthetic organic chemist that successfully synthesized physostigmine. The given statement is True.
Percy Julian was a prominent African American chemist who made significant contributions to the field of organic chemistry, particularly in the area of natural product synthesis.
He is well-known for his synthesis of several important drugs, including physostigmine, but he was not the first to synthesize this compound.
Physostigmine, also known as eserine, was first isolated from the Calabar bean (Physostigma venenosum) in 1864 by the Scottish physician and botanist Sir Thomas Richard Fraser.
Its chemical structure was determined in the early 20th century, and several researchers attempted its synthesis before Percy Julian succeeded in 1935.
So, the statement is partially true, as Percy Julian did synthesize physostigmine, but he was not the first to do so.
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500.0 liters of a gas in a flexible-walled container are prepared at 0.9211 atm and.
200.0 °C. The gas is placed into a tank under high pressure. When the tank cools
to 20.0 °C, the pressure of the gas is 30.0 atm. What is the volume of the gas?
The volume of the gas at 20.0 °C when the pressure of the gas is 30.0 atm is 9.5 liters
How do I determine the volume of the gas?We'll begin by listing out the various parameters given from the question. This is given below:
Initial volume of gas (V₁) = 500.0 litersInitial pressure (P₁) = 0.9211 atmInitial temperature (T₁) = 200.0 °C = 200 + 273 = 473 KFinal temperature (T₂) = 20.0°C = 20 + 273 = 293 KFinal pressure (P₂) = 30.0 atmFinal volume of gas (V₂) = ?The final volume of the gas at 20.0 °C can be obtained by using the combined gas equation as shown below:
P₁V₁ / T₁ = P₂V₂ / T₂
(0.9211 × 500) / 473 = (30 × V₂) / 293
Cross multiply
473 × 30 × V₂ = 0.9211 × 500 × 293
Divide both side by 473 × 30
V₂ = (0.9211 × 500 × 293) / (473 × 30)
V₂ = 9.5 liters
Thus, it is evident from the above calculation that the volume of the gas is 9.5 liters
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Work out the relative formula mass of Mg(OH)2.
Mg(OH)2's relative formula mass is 58.3.
What, using an example, is relative formula mass?The weighted average of the masses of the formula units on a scale where the mass of a carbon-12 atom is exactly 12 units is the relative formula mass of a substance. The "formula unit" is just the formula as it appears on paper, such as NaCl, CuSO4, 5H2O, CO2, or Cl2.
One Mg atom, two O atoms, and two H atoms make up the compound Mg(OH).
For Mg, O, and H, the atomic masses are:
Mg: 24.3
O: 16.0
H: 1.0
Mg(OH)2's relative formula mass is thus:
Relative formula mass of Mg(OH)2 = (1 x relative atomic mass of Mg) + (2 x relative atomic mass of O) + (2 x relative atomic mass of H)
= (1 x 24.3) + (2 x 16.0) + (2 x 1.0)
= 24.3 + 32.0 + 2.0
= 58.3
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how to compare and contrast the properties of cohesion and adhesion
Both cohesion and adhesion involve the attraction between molecules, cohesion refers to the attraction between molecules of the same substance, while adhesion refers to the attraction between molecules of different substances.
Comparison of the two properties are: Definition: Cohesion refers to the attraction between molecules of the same substance, while adhesion refers to the attraction between molecules of different substances.
Forces involved: Cohesion involves intermolecular forces (such as hydrogen bonding) that hold the molecules of the same substance together. Adhesion involves the forces of attraction between two different substances, such as the attraction between water molecules and the surface of a glass.
Surface tension: Cohesion contributes to the surface tension of a liquid, which is the property that allows some insects to walk on water without sinking. Adhesion also contributes to the surface tension, as it causes the liquid to adhere to the surface.
Applications: Cohesion is important in determining the physical properties of liquids, such as their viscosity and boiling point. Adhesion is important in many practical applications, such as adhesives and coatings that need to stick to different surfaces.
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Two students, Will N. Andable and Ben Pumpiniron, are in the weightlifting room. Will
lifts the 100 lb barbell over his head 10 times in one minute; Ben lifts the 100 lb pound
barbell over his head 10 times in 10 seconds. Which student does the most work? Which
student delivers the most power? Explain your answers.
Both students do the same amount of work since they lifted the barbell over their heads the same number of times.
Ben developed more power because he took less time to do the same amount of work.
What is the formula for calculating mechanical power?The formula for calculating mechanical power is given below as follows:
Power = force * distance/time taken
The power of each of the students is calculated as follows:
Assuming the work done by both students is approximated to the weight of the barbell, the power developed by each student will depend only on the time.
Power developed by Will:
Will lifts the 100 lb barbell over his head 10 times in one minute
Ben lifts the 100 lb pound barbell over his head 10 times in 10 seconds
The time taken by Ben to lift the 100 lb pound barbell over his head 10 times in 10 seconds is less than the time taken by Will to lift the 100 lb pound barbell over his head 10 times in 10 seconds, Hence, Ben developed more power.
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Observe the minerals. Describe the mineral's colour, luster (shiny or dull) and the way they break apart (cleavage or fracture) in the student guide
The mineral Calcite has a pale yellow color with a dull luster. It has no visible cleavage.
It appears to have a conchoidal fracture, where the pieces break apart with curved edges.Calcite is a very common mineral composed of calcium carbonate (CaCO3). It is the primary mineral in many metamorphic and sedimentary rocks, and is a major component of limestone and marble. Calcite has a hardness of 3 on the Mohs scale, which makes it suitable for use in jewelry and ornaments. Calcite occurs in a variety of colors, including white, yellow, orange, pink, blue, and green. It is also the main component of many chalk deposits. Calcite is used in many industrial processes and products, including as a filler in cement, as a neutralizing agent in soil, and as a flux in steelmaking. It is also used as a source of calcium in animal feed and as a food additive.
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complete question:Observe the minerals Calcite. Describe the mineral's colour, luster (shiny or dull) and the way they break apart (cleavage or fracture) in the student guide
don't just look at this and don't answer it ._.
yeah i be seeing you guys view the answer and don't do nothing at all, not even comment IoI...
if a reaction is first order with a rate constant of 0.0450 s⁻¹, how much time is required for 65% of the initial quantity of reactant to be consumed?
If a reaction is first order with a rate constant of 0.0450 s⁻¹, 23.3 sec is the time that is required for 65% of the initial quantity of reactant to be consumed.
A first-order reaction in chemistry is a particular kind of chemical process where the rate of the reaction is exactly related to the concentration of just one ingredient. With respect to that specific reactant, the reaction rate is referred to as first-order.
First order rate law is given by,
A = A0 × [tex]\rm e^{-kt}[/tex]
A0 = Initial concentration=100 M
A = Final concentration=35 M (65% is consumed means 35% is the remaining compound)
K = Rate constant = 0.0450 [tex]\rm s^{-1}[/tex]
Substituting,
35 = 100 × [tex]\rm e^{-0.0450 \times t}[/tex]
e-0.0450×t = 0.35
- 0.0450×t = ln(0.35)
-0.0450×t = -1.05
t = 23.3 sec
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What is the role of catalysts in chemical reactions and how do they affect reaction rates?
Answer:
catalysts increase the rate of reaction
Explanation:
Answer:
Catalysts play a key role in chemical reactions by lowering the activation energy required for the reaction to occur. By doing so, catalysts increase the rate of reaction and can help make chemical reactions occur under milder conditions.
Explanation:
e-85 is an alternative fuel for automobiles and light trucks that consists of 85.0% (by volume) ethanol (c2h5oh), and 15.0% gasoline. when ethanol burns completely it produces co2 and h2o. the balanced equation for the burning of ethanol is
When ethanol burns completely it produces CO2 and H2O, 993.2 moles of CO2 are used.
Given that,
E-85 is an alternative fuel for automobiles and high trucks consisting of 85.0% Ethanol =15.0% gasoline.
C2H5OH+3O2----> 2CO2+3H2O
The density of ethanol = 0.790 g/mL
1 gallon = 3.785 L
therefore, 9 gallons = 9*3.785
=34.07 L
Volume of ethanol in 9 gallons=85% of 34.07 L.
=85/100*34.07
=28.96 L
Mass of ethanol = Volume * Density
=28.96 L*0.790 g/mL
=22878.49 g
Moles of ethanol= Mass/ molar mass
=22848.49/46.07 g/mol
=496.6 moles
Thus, the moles of CO2 produced = 2*496.6 = 993.2 moles of CO2.
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What level of protein structure describes the spatial location of every atom in a protein? Choose one:
A. 0'
B. 2'
C. 1'
D. 3'
neurons communicate with each other through the use of chemical messengers called
The correct answer is Neurotransmitters are chemical messengers that are essential for your body to function.
To affect another cell across a synaptic gap, a neuron produces a chemical signaling agent known as a neurotransmitter. Any significant organ, target cell, gland, or muscle cell that receives the signal might be another neuron as well. Neurotransmitters are released from synaptic vesicles in the synaptic cleft, where they may interact with receptors on the target cell. The neurotransmitter's impact on the target cell depends on the receptor to which it binds. From readily available, plentiful precursors like amino acids, which are regularly transformed in a few biosynthetic steps, several neurotransmitters are created.
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Assume you are working with an acutely toxic chemical
Administrative controls to consider when working with an acutely toxic chemical include:
1. Establishing and implementing safe operating procedures (SOPs).
2. Providing staff with appropriate safety training.
3. Establishing a clear chain of command and communication system to ensure staff are aware of any potential risks associated with the chemical.
4. Establishing a system for reporting any incidents, accidents, or other issues related to the chemical.
5. Ensuring adequate ventilation and other engineering controls for the chemical.
6. Monitoring the toxic chemical for any signs of contamination or degradation.
7. Restricting access to the chemical to only those with the appropriate safety training.
8. Implementing appropriate personal protective equipment (PPE).
9. Providing frequent safety inspections of working areas and equipment.
10. Implementing a system for disposing of the chemical in a safe manner.these are the administrative controls relevant for project.
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complete question:Assume you are working with an acutely toxic chemical; give all administrative controls relevant for your project.
elements x has a ground state electron configuration of ns2np5. what is the most likely formula for the compound composed of element x and nitrogen?
The most likely formula for the compound composed of element x and nitrogen is CX₄
Element X has a ground- state valence electron configuration of ns2np5
It'll partake one electron to complete its quintet. therefore, it'll form one covalent bond. C snippet shares 4 electrons to complete its quintet. Hence, C snippet forms 4 covalent bonds. therefore, one C snippet will combine with 4 X tittles. The formula of the carbon emulsion most likely to be formed is CX4.
An ionic compound is formed when two atoms combine and one atoms transfers electron to the other atom. Ionic bonds are usually formed between metals and nonmetals.
The element M has two valence electrons and has a valency of two while the element X has seven valence electrons and a valency of one. Hence, the formula of the ionic compound that would most likely result from the reaction between ions of M and X is MX₄.
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Which type of plate boundary is the student modeling? Explain your answer.
The "convergent plate boundary" is the kind of plate boundary that the student is simulating.
What does word boundary mean?This zero-width check between two letters identifies a word boundary. A word character and a non-word letter must be present for the test to be successful. Each figure must appear on one side, regardless of which side they are on.
What are examples of word boundaries?For illustrate, the "three little pigs" went to the market. Indivisibility: Specify a statement and request that someone "add extra words" to it. This additional item will be entered between the words, not before or after them.
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Which requires less energy, recycling existing Al or extracting Al from Al2O3? Justify your answer with a calculation
Use math to support your response. 837.5 kJ are needed to produce 1.00 mol of aluminum from Al2O3. Recycling needs less energy since 26 kJ 837.5 kJ.
Recycling aluminum saves 95% more energy than manufacturing it from scratch. Additionally, 97% of the greenhouse gas emissions generated during primary production are avoided. Aluminum is created from bauxite, which is also recycled, saving 9 tonnes of CO2 emissions and 4 tonnes of bauxite production. Since aluminum can be recycled indefinitely and uses up to 95% less energy when recycled than when produced as primary aluminum, it reduces emissions, including greenhouse gas emissions. Nearly a billion tons, or over 75%, of the aluminum produced throughout history is still in use.
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the combustion of a hydrocarbon sample produced 0.1783 g of co2 and 0.0734 g of h2o. determine the empirical formula of the compound.
The empirical formula of the compound is CH2O.
The empirical formula of a compound is determined by dividing the mass of each element by its molar mass and then simplifying the resulting ratio to the smallest whole-number ratio.
The molar mass of CO2 is 44.01 g/mol.
Therefore, 0.1783 g of CO2 would be equivalent to 0.0040 mol CO2.
For H2O, the molar mass is 18.02 g/mol.
Therefore, 0.0734 g of H2O would be equivalent to 0.0041 mol H2O.
Therefore, the ratio of the elements would be 0.0040 mol CO2: 0.0041 mol H2O.
Simplifying this ratio to whole numbers yields 1 mol CO2: 1 mol H2O.
As a result, CH2O serves as the compound's empirical formula.
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What are the 3 atoms made of?
Atoms are composed of three main types of particles: protons, neutrons, and electrons.
Protons are positively charged particles found in the nucleus (center) of an atom. The number of protons in an atom's nucleus is referred to as its atomic number and determines what element the atom is.
Neutrons are neutral particles also found in the nucleus. They help to hold the protons together in the nucleus and add mass to the atom.
Electrons are negatively charged particles that orbit the nucleus in shells or energy levels. The number of electrons in an atom is equal to the number of protons, so atoms are electrically neutral. The arrangement of electrons in an atom determines its chemical properties and reactivity.
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What mass of sodium iodide (NaI) will react with 7.82 grams of chlorine?
16.49g sodium iodide (NaI) will react with 7.82 grams of chlorine.
Given, Mass of Chlorine gas = 7.82g
Mass of sodium iodide = ?
Let's find the number of moles of the given element:
Number of moles = mass/molar mass
Molar mass of Cl₂ = 2(35.5) = 71g/mol
Number of moles = 7.82/71 = 0.11mole
The given reaction equation is:
2NaI + Cl₂ → 2NaCl + I₂
Here, 2 mole of Cl₂ will react with 2 mole of NaI
Also, 0.11 mole of Cl₂ will also react with 0.11mole of NaI
Mass of sodium iodide = number of moles x molar mass
Molar mass of NaI = 23 + 126.9 = 149.9g/mol
Mass of sodium iodide = 0.11 x 149.9 = 16.49g
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The complete question is -
What mass of sodium iodide (NaI) will react with 7.82 grams of chlorine? 2NaI + Cl₂ → 2NaCl + I₂ (given reaction equation).
What is the major product of a reaction?
In chemistry, the term "major product" refers to the product of a chemical reaction that is formed in the highest yield
Meaning that it is produced in the greatest amount compared to other products that may also be formed in the reaction. The major product is often determined by considering the thermodynamics of the reaction, as well as the reaction kinetics and any other factors that may influence the distribution of products. The identity of the major product can be predicted based on the reaction conditions and the reactants involved, and is an important factor to consider in the design of chemical syntheses and the optimization of reaction conditions.
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will increasing the partial pressure of the reactants increase the production of ammonia from nitrogen gas and hydrogen gas?
Yes, increasing the partial pressure of the reactants will increase the production of ammonia from nitrogen gas and hydrogen gas.
This is because the rate of the reaction is directly proportional to the partial pressures of both the reactants. As the partial pressure of the reactants increases, the rate of the reaction increases, and therefore more ammonia is produced. The reaction equation is as follows:
N2 + 3H2 → 2NH3
The equation: gives the rate of this reaction.
Rate = k[N2][H2]3
where k is a rate constant and [N2] and [H2] are the partial pressures of nitrogen gas and hydrogen gas, respectively.
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Rank these elements from strongest to weakest Columbia attraction
Neon, Lithium, potassium, radon, helium, nitrogen, Praseodymium, aluminum
from strongest to weakest Columbia attraction these elements are Neon, Lithium, Potassium, Radon, Helium, Nitrogen, Aluminum, Praseodymium.
What is Columbia attraction?Columbia attraction is a type of intermolecular force that takes place between two molecules. This force is typically weak and is the result of electrostatic attraction between molecules. It is often referred to as London Dispersion Force (LDF) or van der Waals force. Specifically, Columbia attraction occurs when electrons in one molecule are not evenly distributed and become attracted to the nucleus of another molecule. This causes the two molecules to become attracted to one another, creating a weak force of attraction. This force is important for a variety of reasons, such as allowing for molecules to form liquids, solids, and even gases. It also plays a role in allowing for chemical reactions to take place as well as allowing for molecules to interact with one another. Columbia attraction is an essential force in the world of chemistry and plays a major role in helping us understand how molecules interact with one another.
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What is an example of emission spectra?
An emission spectrum is a spectrum of light emitted by a substance, such as a gas or a solid, that is excited by heating or some other form of energy input.
The light emitted by the substance is characteristic of its composition and atomic structure, and can be used to identify the substance and determine its chemical composition.
An example of an emission spectrum is the spectrum of light emitted by a hydrogen gas. When hydrogen gas is excited by an electric discharge, it emits light in the form of a series of bright lines, each with a characteristic wavelength. This series of bright lines is known as the hydrogen emission spectrum, and it is used to identify the presence of hydrogen in a sample and determine its concentration.
Another example of an emission spectrum is the spectrum of light emitted by a neon sign. When a high voltage is applied to a tube filled with neon gas, the gas emits a characteristic red light. This light is produced by the emission of photons from the excited neon atoms, and the spectrum of light emitted is unique to neon.
In conclusion, an emission spectrum is a spectrum of light emitted by a substance that is excited by heating or some other form of energy input, and it is used to identify the substance and determine its chemical composition.
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The molecular formula of an antibacterial drug is C, H, FN,O,. How many fluorine atoms are in a 150-mg tablet of this drug?
Answer:
To find the number of fluorine atoms in a 150-mg tablet of the antibacterial drug, you need to know the molecular weight of the drug and the number of moles in 150 mg.
Since the molecular formula is given as C, H, F, N, O, you can determine the molecular weight by adding the atomic weights of each element.
For example, if the atomic weights of C, H, F, N, and O are 12, 1, 19, 14, and 16, respectively, the molecular weight of the drug is (12 x C) + (1 x H) + (19 x F) + (14 x N) + (16 x O).
Knowing the molecular weight and the number of moles, you can use Avogadro's number to find the number of fluorine atoms. Avogadro's number is 6.022 x 10^23.
Since the information about the molecular weight, number of moles, and molecular formula is not given, it's not possible to determine the number of fluorine atoms in a 150-mg tablet of this drug.
Explanation:
According to Avogadro's number, there are 0.0145×10²³ atoms present in a 150-mg tablet of this drug.
What is Avogadro's number?Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.
It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .
According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.
Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number, substitution of values in formula gives number of atoms= 0.15/62×6.022×10²³= 0.0145×10²³.
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the initial concentration of a reactant in a first order reaction is 0.860 m. what will be its concentration after 4 half-lives have passed?
concentration of the reactant after 4 half-lives have passed will be 0.0538 M.
In a first-order reaction, the rate of the reaction is directly proportional to the concentration of the reactant. The formula to calculate the concentration of a reactant after a certain number of half-lives is:
C_final = C_initial * (1/2)^n
Where C_initial is the initial concentration, n is the number of half-lives, and C_final is the final concentration.
For a first-order reaction, the half-life is constant and can be calculated using the following formula:
t1/2 = 0.693/k
Where k is the rate constant.
If 4 half-lives have passed, the concentration of the reactant will be:
C_final = C_initial * (1/2)^n
C_final = 0.860 M * (1/2)^4
C_final = 0.0538 M
Therefore, the concentration of the reactant after 4 half-lives have passed will be 0.0538 M.
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the ph of a certain weak acid solution with a concentration of 0.150 m is 2.535. what is the ka for this acid?
The Ka for the weak acid is 9.14 x 10^(-6).
Weak acid isA weak acid is an acid that only partially dissociates in water, and its strength is described by its acid dissociation constant (Ka).
To determine the Ka for the weak acid, we can use the relationship between the Ka and the pH of the solution:
Ka = 10^(-pH) * [HA]/[A-]
where [HA] is the concentration of the undissociated weak acid and [A-] is the concentration of the conjugate base.
From the given information, we know that the pH of the solution is 2.535. This means that:
[H+] = 10^(-pH) = 10^(-2.535) = 3.62 x 10^(-3) M
Since the acid is weak, we can assume that the concentration of the undissociated weak acid ([HA]) is approximately equal to the initial concentration of the acid (0.150 M).
Next, we can use the equation for the dissociation of the weak acid:
HA + H2O ⇌ H3O+ + A-
to write an expression for the equilibrium constant (Ka):
Ka = [H3O+][A-]/[HA]
We can use the fact that the solution is electrically neutral to write:
[H3O+] = [A-] + [OH-]
where [OH-] is the concentration of hydroxide ions.
Since the acid is weak, we can assume that the concentration of hydroxide ions is much smaller than the concentration of hydronium ions, so we can approximate:
[H3O+] ≈ [A-]
Substituting these expressions into the equation for Ka, we get:
Ka = [H3O+]^2 / [HA]
Plugging in the values we have calculated, we get:
Ka = (3.62 x 10^(-3))^2 / 0.150
Ka = 9.14 x 10^(-6)
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