Answer:
What is the valency of elements in the group 'v' of the modern periodic table?
Answer: -3
What is the reasons for the fact that reactivity of group 'v' elements decrease as we go down in the group?
Answer: On moving down the group, there is a decrease in the electron affinity of elements. It is because, as the size of an atom increases, the valence electrons get further away from its nucleus. Thus, the attraction between them decreases.
The half-life of strontium-90 is 28 years. how long will it take a 100-mg sample to decay to a mass of 56 mg? (round your answer to the nearest whole number.)
The half-life of strontium-90 is 28 years. It will take 52 years a 100-mg sample to decay to a mass of 56 mg.
What is half life period?A half-life is just the amount of time it takes for something to go from 100% to 50%. The phrase is most frequently used in reference to radioactive decay, which happens when energetic atomic particles that are unstable lose momentum. There are 29 elements that have been shown to be susceptible to going through this process.Number of half lives that have passed is n, and the fraction that is left is equal to 0.5n.
Given that one half life is equal to 28 years, we must find n in this situation, and the remainder will be equal to 16/56, or 0.28.
0.28 = 0.52^n n = 2
after 1 half life = 0.52 remains.
after 2 half lives= 0.28 remains
Therefore, one half life is 28 years, it will take two half lives for 56 mg to decompose into 16 mg, which is equal to 52 years.
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Which waxy molecule, found in the cell wall of acid-fast bacteria, prevents these cells from being gram stained?.
Mycolic acids are found in the cell wall of acid-fast bacteria, preventing these cells from being gram-stained.
Acid-fast bacteria are a kind of bacteria that contains waxy material called mycolic acid in their cell wall making them water-resistant against staining procedures and materials such as gram stain.
Mycolic acids are lengthy chains of fatty acids found in bacteria and, therefore, are called acid-fast bacteria.
When these bacteria come into contact with substances like acidic alcohol, they develop resistivity against them to prevent decolorization.
In short, mycolic acids prevent the decolorization and staining of bacteria due to their characteristics of resistance and reluctance.
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What+is+the+molar+fraction+of+25%+w/w+acetic+acid+solution?+(density+=+1.05kg/l,+mw+=+60)+answer+(0~1)
The molar fraction of 25% w/w acetic acid solution is 0.069.
The molar fraction of solute in a solution is given by the following formula
Molar fraction of solute = No. Of Moles of solute/No. Of Moles of solute + No. of Moles of solvent
In this case the solute is acetic acid and solvent is water.
It is given that the acetic acid is 25% weight by weight(w/w), which means that 25 grams of acetic acid is present in 100 grams of water.
To calculate the moles, we need to divide the given mass by the molar mass of the compound
No. of moles of Acetic Acid(CH3COOH)= 25/60 = 0.416
And no. of moles of water (H2O) = 100/18 = 5.55
Putting the values in the given formula
Molar fraction of solute = 0.416/5.55+0.416
= 0.069
Hence, the molar fraction of 25% w/w acetic acid solution is 0.069.
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Draw the structure for 1,3-dinitrocyclopentane, making sure to add all non-zero formal charges
In the image provided below, you can see the structure of 1,3-dinitrocyclopentane.
We can conclude the following information from the compound's name, 1,3-dinitrocyclopentane, which will assist us in drawing the structure :-
1,3 - position of NO₂ groups, di - two, nitro - NO₂, clo - cyclic, pentane - five.
➤ The following are the general steps for drawing any compound's Lewis structure:
Calculate the number of carbons and hydrogens.Connect the carbons with one another.Add the hydrogens and check that each carbon has four bonds and thus meets the octet rule.According to the Octet Rule almost all atoms, in this case, carbon must always have four bonds because they are most stable with eight total electrons.
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A solution is made by mixing of heptane and of acetyl bromide . calculate the mole fraction of heptane in this solution. round your answer to significant digits.
The mole fraction of acetyl bromide is 0.534 and heptane is 0.466.
What is acetyl bromide?An acyl halide, sometimes referred to as an acid halide, is a chemical molecule created by swapping out the hydroxyl group in an oxoacid with a halide group.
The chemical has a -COX functional group, which is made up of a carbonyl group that is singly linked to a halogen atom, if the acid is a carboxylic acid. The general formula for such an acyl halide can be represented as RCOX, where X stands for the halide, such as chloride, and R may be, for example, an alkyl group. Although acyl chlorides are the most frequent acyl halides, acetyl iodide is the one that is created (temporarily) on a big scale. The annual manufacturing of acetic acid results in billions of kilograms.
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explain the energy and intermolecular forces that are involved for liquid solid and gas
The energy and intermolecular forces involved for liquid solid and gas are as follows:
Solids: solids have strong intermolecular forces and low kinetic energy.Liquids: liquids have weak intermolecular forces and high kinetic energy.Gases: gases have negligible intermolecular forces and very high kinetic energy.What are intermolecular forces?Intermolecular forces are forces of attraction that exists between the molecules of a substance.
The strength of the intermolecular forces and hence, the kinetic energy vary inversely in molecules of solids, liquids and gases.
The energy and intermolecular forces that are involved for liquid solid and gas are explained below:
Solids: solids have strong intermolecular forces and low kinetic energy. Thus solids have definite shapes and volume.Liquids: liquids have weaker intermolecular forces and higher kinetic energy than solids.Gases: gases have negligible intermolecular forces and very high kinetic energy.In conclusion, intermolecular forces decrease with increase in the kinetic energy of molecules.
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A protein mixture is commonly applied to an hic column under high ___ conditions, and the protein of interest is eluted with buffer of decreasing ____.
A protein mixture is commonly applied to a HIC column under high salt conditions, and the protein of interest is eluted with a buffer of decreasing ionic strength.
Structured salts added to the equilibration buffer and sample promote ligand-protein interactions in HIC. The amount of bound protein decreases as the salt concentration decreases, as does the risk of protein precipitation at lower ionic strength.
Despite the fact that sodium, potassium, or ammonium sulfates have a higher precipitation effect, these salts effectively promote ligand-protein interactions in HIC. Most bound proteins are eluted by washing with water or a dilute buffer with a pH close to neutral.
What exactly is HIC?
Hydrophobic interaction chromatography (HIC) is a technique used to separate molecules based on their hydrophobicity. HIC is a useful separation technique for purifying proteins while retaining biological activity due to the use of less denaturing conditions and matrices.
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An ion is a____version of an atom that is formed by____compared to the atom.
An ion is a charged version of an atom that is formed by losing or gaining electrons compared to the atom.
Cations are positively charged atoms.
Anions are negatively charged atoms.
For example, calcium atom forms cation.
Electron configuration of calcium atom: ₂₀Ca 1s² 2s² 2p⁶ 3s² 3p⁶ 4s².
Electron configuration of calcium cation: ₂₀Ca²⁺ 1s² 2s² 2p⁶ 3s² 3p⁶.
Calcium cation is smaller than neutral calcium atoms, because when an electrons are lost, electron-electron repulsion decreases and the protons are better able to pull the remaining electrons towards the nucleus.
When calcium loose two electrons, it will have 20 protons (positive charge) and 18 electrons (negative charge), which means it has two protons more and it has +2 oxidation number.
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3. Carbon reacts with oxygen to produce carbon dioxide: C+ O₂ → CO₂. Calculate the mass of carbon required to produce
17.6 g of carbon dioxide. (Relative atomic masses: C = 12,0=16)
[4 marks]
mass of carbon
Answer :
?
the mass of carbon required to produce
17.6 g of carbon dioxide will be 6 gram.
The weighted average of the molecular masses of a material, measured on a scale where a carbon-12 atom has a mass of precisely 12 units, is the substance's relative molecular mass.The number of atoms in exactly 12 grams of pure carbon-12 is the value of a mole.An exothermic process occurs when carbon and oxygen combine to form carbon dioxide, which generates 394 kJ/mol of heat.In the reaction,
C+ O₂ → CO₂
Given,
The atomic mass of Carbon is 12g/mol
molar mass of O2 is 32g/mol
1 mole of C get reacted with 1 mole of O2.
no. of moles in O₂ = 16/32 = 0.5
so, 0.5 moles of Ow will react with 0.5 moles of C
Moleculer weight of Carbon is 12
Mass of carbon = 0.5 × 12 = 6 gm
Hence, mass of carbon required is 6 g.
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What type of signaling molecules are the incretins? autocrine signals paracrine signals juxtacrine signals classic hormones
1. what mass of solid cocl2 would you need, to prepare 250 ml of 0.150 m solution of cocl2 from solid cocl2 and distilled water? show your calculations.
The quantity of matter in an item is its mass. Scientists frequently use balances to quantify mass. Using an electronic balance or a beam balance, one may directly determine the mass of solids.
What is meant by mass of solid?
The quantity of matter in an item is its mass. Scientists frequently use balances to quantify mass. Using an electronic balance or a beam balance, one may directly determine the mass of solids. A liquid's mass can be calculated by measuring its volume and using the density table to determine the liquid's density.
The kilograms is the SI unit of mass (Kg). To get an object's mass, divide its weight by the acceleration of gravity. The weight units must be changed to Newtons. For instance, 1 kg equals 9.807 N. If you want to know an object's mass on Earth, divide its weight in Newtons by the Earth's gravitational acceleration, which is 9.8 meters per second2.
Here, solute is solid cocl2 and our solvent is distilled water.
The volume of solute is generally ignored, so we would dissolve,
[tex]$250 \mathrm{~mL} \cdot \frac{\mathrm{L}}{10^3 \mathrm{~mL}} \cdot 0.150 \mathrm{M} \cdot \frac{129.9 \mathrm{~g}}{\mathrm{~mol}} \approx 5.68 \mathrm{~g}$[/tex]
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How many Cl atoms are in 0.0467 g of PCl₃?
Answer:
The answer is there are 9.57 x 10²⁰ number of Cl atoms in 0.0728 g of PCl₃.
Number of moles = mass / molar mass
Mass of PCl₃ = 0.0728 g and molar mass of PCl₃ = 137.33g/mol
Number of moles of PCl₃ = 0.0728 / 137.33 = 5.3 x 10⁻⁴
In one mole there are Avogadro’s number of molecules that is 6.02 x 10²³
So, in 5.3 x 10⁻⁴ moles of PCl₃, there are =5.3 x 10⁻⁴ x 6.02 x 10²³ = 3.19 x 10²⁰
Now there is 3 atoms of Cl in PCl₃ so in 3.19 x 10²⁰ molecules of PCl₃, number of Cl atoms = 3.19 x 10²⁰ x 3 = 9.57 x 10²⁰ atoms
In the given three dimensional molecular structure the differently colored spheres represent different types of atoms. Write a molecular formula for this model
Answer: penlalalalaooooaaaaaaaaaaa
Explanation: pen
The electronic configuration of an ion is 2.8.8. What could this ion be?
Answer: The answer Option is A.
Explanation: Both the Ions have the electronic configuration 2,8,8
The electronic configuration of an ion is 2.8.8. This ion is S²⁻.
What is an electronic configuration ?The term electronic configuration is defined as the arrangement of electrons in orbitals around an atomic nucleus.There are four different types of orbitals (s,p,d, and f) have different shapes, and one orbital can contain a maximum of two electrons.
The symbols used for writing the electron configuration start with the shell number (n) and then the type of orbital and finally the superscript represent how many electrons are present in the orbital.
The electronic configuration of an ion is 2.8.8. This ion is S²⁻. Because S²⁻ contain electronic configuration of an ion is 2.8.8 while electronic configuration of S is 2, 8, 6.
Thus, The electronic configuration of an ion is 2.8.8. This ion is S²⁻.
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What is the oxidation state of co in [co(oh2)6]2?
Correct compound is [Co(H2O)6]^+3
The oxidation state of Co is +3
[Co(H2O)6]^+3
Let
Co be x
H2O = 0
x + (0)6 = 3
x = 3
What is oxidation state?
The oxidation state, commonly known as the oxidation number, is the potential charge that an atom would have if all of its bonds to other atoms were fully ionic. It describes the degree of atom oxidation within a chemical compound.The oxidation state may be positive, negative, or zero in theory.
The oxidation number, sometimes referred to as the oxidation state, is the total number of electrons that an atom gains or loses while uniting with another atom to form a chemical bond.
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If 8.4 moles of disilane, si2h6 are combined with 15.1 moles of o2, which is the limiting reactant ?
Oxygen (O₂) is the limiting reactant.
Balanced chemical equation for reaction of disilane with oxygen:
2Si₂H₆ + 7O₂ → 4SiO₂ + 6H₂O.
Word equation: disilane + oxygen → silicon dioxide + water.
n(Si₂H₆) = 8.4 mol; amount of disilane
n(O₂) = 15.1 mol; amount of oxygen
From balanced chemical equation: n(Si₂H₆) : n(O₂) = 2 : 7
mole ratio for disilane = 8.4 mol / 2 = 4.1 mol
mole ratio for oxygene = 15.1 mol / 7 = 2.15 mol
Oxygen is the limiting reactant, because it has smaller mole ratio than disilane.
Limiting reactant determine amount of the product formed in a reaction.
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A compound is analyzed and found to contain 92.24% carbon, 7.76% hydrogen. Calculate the
mass of the compound that contains 185.0 g of hydrogen.
The mass of the compound that contains 185.0 g of hydrogen is 2384.02 g
Data obtained from the questionThe following data were obtained from the question:
Percentage of carbon = 92.24%
Percentage of hydrogen = 7.76%
Mass of hydrogen = 185.0 g
Mass of compound =?
How to determine the mass of the compoundThe mass of the compound can be obtained as illustrated below:
Percentage of hydrogen = (mass of hydrogen / mass of compound) × 100
7.76% = 185 / mass of compound
0.0776 = 185 / mass of compound
Cross multiply
0.0776 × mass of compound = 185
Divide both sides by 0.0776
Mass of compound = 185 / 0.0776
Mass of compound = 2384.02 g
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Combining aqueous solutions of bai2 and na2so4 affords a precipitate of baso4. which ions are spectator ions in the reaction?
a. so42- and i-
b. ba2 only
c. na and i-
d. ba2 and so42-
.e na only
The spectator ions are Na+ and I when mixing aqueous solutions of BaI2 and Na2SO4 to create a precipitate of BaSO4.
What are spectator ions?
Spectator ions are ions that are present on both sides of chemical reactions but do not take part in the reaction itself. In the net chemical reaction, the spectator ions on both sides of the equation are cancelled. So, to "spectate" is to "see" the other ions in an aqueous solution interact with one another.
The spectator ions are Na+ and I when mixing aqueous solutions of BaI2 and Na2SO4 to create a precipitate of BaSO4.
Let's look at the chemical formula for the reaction that happens when BaI2 and Na2SO4 are combined in aqueous solution. This reaction involves two displacements.
BaSO4(s) + 2 NaI = BaI2(aq) + Na2SO4(aq) (aq)
Let's now have a look at the net ionic equation, which takes into account both the insoluble species and the reacting ions (not spectator ions).
Ba2+(aq) SO42(aq) BaSO4 (s)
As we can see, Na+ and I are the spectator ions that are missing from the net ionic equation.
The spectator ions are Na+ and I when mixing aqueous solutions of BaI2 and Na2SO4 to create a precipitate of BaSO4.
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If you put a strong acid in 100 ml of water and then you put the same amount of a weak acid in 100 ml of water, why would the ph be lower in the beaker with the strong acid?
The pH be lower in the beaker with the strong acid because strong acid gives more hydrogen ions.
pH (potential of hydrogen) is a numeric scale used to specify the acidity or basicity an aqueous solution.
When pH is less than seven (pH<7), solution is acidic.
Hydrochloric acid is strong acid and in water dissociates completely:
HCl(aq) → H⁺(aq) + Cl⁻(aq)
Amount of hydrogen ions are the same as amount of hydrochloric acid.
At other hand, acetic acid (CH₃COOH) is weak acid and does not dissociate completely as HCl, so concentration of hydrogen ions in a solutions are very low.
Strong acids: HNO₃(nitric acid), HCl(hydrochloric acid), H₂SO₄(sulfuric acid), HI(hydroiodic acid).
Weak acids:CH₃COOH (acetic acid), H₂CO₃ (carbonic acid), HCN (cyanic acid).
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If+a+student+needed+to+make+25.678g+alum+and+koh+and+h2so4+are+in+excess,+how+much+al+should+the+student+start+with+knowing+that+they+would+only+get+an+80%+yield+of+alum
Al is equal to 0.0463 moles of aluminum in 1.25 grams.
The ratio of aluminum to alum is 1:1, meaning that for every mole of aluminum consumed, 1 mole of alum is created.
The calculated yield is 21.96 g of alum.
Yield as a percentage is 68.97%.
What is alum?Acute and chronic oral LD50 values for aluminum sulfate are both more than 5,000mg/kg, making it relatively non-toxic. Alum can nonetheless irritate the skin, burn, and worsen respiratory conditions. It can lead to headaches, nausea, and respiratory irritations when breathed.
It is an astringent, which means it causes the skin to constrict or shrink, first of all. Astringents have the short-term ability to shrink pores and tighten skin. Alum is a helpful preservative because it is bacteriostatic, which means it inhibits the growth of bacteria.
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What types of catalyst is called a postive catalyst?
Answer:
Positive catalysts are those catalysts which increase the rate of the reaction This means that the activation energy of the reaction is lowered, and the speed of the reaction also increases. An example of positive catalysis is decomposition of potassium chlorate.
Explanation:
A forensic scientist is attempting to identify a type of plastic found at a crime scene. What test could she conduct on the plastic to observe its chemical properties?
Break the plastic into pieces
Dissolve the plastic in water
Add acid to the plastic to see if it reacts
Observe the plastic under a microscope
The chemical properties could be obtained by adding acid to the plastic to see if it reacts.
What are chemical properties?Chemical properties are those properties that could only be observe when a substance undergoes chemical change. In this case, a chemical change could also be called a chemical reaction.
A substance could be said to undergo a chemical reaction if there is a rearrangement of the atoms of the compound. This would ultimately lead to the formation of a new substance.
Now the forensic scientist wants to know the chemical properties of the plastic. This could be done by reacting the plastic with acid.
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Answer:
The short answer is (C) Add acid to the plastic to see if it reacts
Explanation:
Got it right on my quiz.
Question 1: (answer in place of item 16)
Apple juice has a pH of around 3 and lemon juice has a pH near 2. If you were trying to neutralize the acid of these fruit juices for baking, which juice would need more baking soda? Why?
(Extra Credit: if the apple juice needed .21 g of soda to neutralize it,
how much soda would an equal quantity of lemon require?)
Question 2:(answer in place of item 17)
What is a mole and what is molarity? How are these ideas similar and how are they different?
Question 3:(answer in place of item 18)
Hexane is a non-polar solvent and ethanol is a polar solvent.
Which of these would you choose to dissolve an ionic salt like LiCl? Why?
Question 4:(answer in place of item 19)
The pH of a solution has a big effect on the speed of some reactions and some reactions only happen in a certain pH range. Why is acid base chemistry important for medicine?
1. Apple juice has a pH of around 3 and lemon juice has a pH near 2. to neutralize with baking soda lemon juice would need more baking soda because it is more acidic than aple juice. the less ph present the more baking soda need to neutralize.
2. A "mole" is the quantity of a material that is precisely 6.02214076 X 1023 particles in the International System of Units. Ions, atoms, or molecules might make up the particles.
The number of moles of a solute in a litre of solution is known as molarity (M). The symbol for molarity is M, which stands for mole/liter.
Molarity is a measure of a solution's concentration that is expressed in units of moles per litre. Therefore, molarity is utilised to calculate the solute's volume.
3 Hexane will dissolve in ionic salt like LiCl because both of the compound are covalent and non-polar and like dissolves like.
4.Every enzyme has a preferred pH range. Outside of this range, pH changes will limit enzyme activity. Enzymes can denature at extreme pH levels. If there is a substrate available for the enzyme to bind to, increasing the concentration of the enzyme will hasten the process.
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What is the experimental quanity that serves as a measure of resistance to flow of a liquid?
Viscosity is the experimental parameter used to assess a liquid's resistance to flow.
What is Viscosity?Viscosity is the ability of a fluid (liquid or gas) to resist changing its shape or allowing nearby parts to move in relation to one another. Viscosity is a sign of flow resistance.
The fluidity, a metric indicating the ease of flow, is the reciprocal of viscosity. For instance, molasses is more viscous than water.
The viscosity of a liquid is a significant metric because the user may interpret it as a gauge of quality; in some cases, a thicker liquid may be perceived as having higher quality than a thinner one.
The texture of food also has a property called viscosity.
Therefore, viscosity is the experimental quality that serves as a measure of resistance to flow of a liquid.
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A graduated cylinder which has been filled with 20. 00 ml of water. A solid object is added to the graduated cylinder and the water level rises to the 26. 40 ml. Calculate the mass (in grams) of the solid object which has a density of 3. 26 g/ml
The solid object that has a density of 3.26 g/ml has a mass equal to 20.864 g.
If the water level rises to 26.40 ml from an initial of 20.00 ml after a solid object is added, then the difference between the final and initial volume of water is the volume of the solid.
volume of solid = final volume - initial volume
volume of solid = 26.40 ml - 20.00 ml
volume of solid = 6.40 ml
If the solid object has a density of 3. 26 g/ml and a volume of 6.40 ml, using the formula for density, solve for its mass.
density = mass/volume
3. 26 g/ml = mass/6.40 ml
mass = 3. 26 g/ml(6.40 ml)
mass = 20.864 g
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The hydrate compound c u s o 4 ⋅ 5 h 2 o is blue in color, while the dehydrated form of copper sulfate c u s o 4 is white. What procedure do you think could be used to convert the pentahydrate form to the dehydrated form?.
Answer:
Evaporate a solution of CuSO4⋅5H2O to dryness
Explanation:
To dehydrated you have to get rid of the water and water evaporates so you have to evaporate the solution.
Procedure that could be used to convert the pentahydrate form to the dehydrated form is to evaporate a solution of CuSO₄⋅5H₂O to dryness.
Copper(II) sulfate pentahydrate (CuSO₄·5H₂O) form aqueous solutions of bright blue.
After the heating, dehydrated form copper(II) sulfate is formed.
Salt copper(II) sulfate has white color.
Adding a water in white copper(II) sulfate would make solution blue again.
Hydrate is a substance that contains water or its constituent elements.
M(CuSO₄·5H₂O) = 249.5 g/mol; molar mass of copper sulphate pentahydrate
Evaporation occurs when the molecules at the surface of a liquid gain enough energy to overcome the force of attraction of other molecules in the liquid phase.
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If you burn 39. 3 g of hydrogen and produce 351 g of water, how much oxygen reacte?
312 grams of oxygen reacts.
Balanced chemical equation for the reaction of hydrogen and oxygen to produce water: 2H₂ + O₂ → 2H₂O.
m(H₂) = 39.3 g; mass of hydrogen
n(H₂) = m(H₂) ÷ M(H₂).
n(H₂) = 39.3 g ÷ 2 g/mol.
n(H₂) = 19.65 mol; amount of hydrogen
m(H₂O) = 351 g; mass of water
n(H₂O) = 351 g ÷ 18 g/mol
n(H₂O) = 19.5 mol; amount of water
From chemical equation: n(O₂) : n(H₂O) = 1 : 2
n(O₂) = 19.5 ÷ 2
n(O₂) = 9.75 mol; amount of oxygen
m(O₂) = 9.75 mol × 32 g/mol
m(O₂) = 312 g; mass of oxygen
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1
2
13
4 points
How many significant figures are in 526.00
How many moles of copper were in the copper oxide formed? the molar mass of copper(ii) sulfate pentahydrate is 249.68 g/mol. for best accuracy, use the mass measurements read using the balance.
79.91 g moles of copper were in the copper oxide formed.
Using the molar mass of 125.00 grams of copper (II) sulfate pentahydrate (CuSO45H2O), we first determine how many moles there are:
(Molar Mass of CuSO4) + 5*(Molar Mass of H2O) = Molar Mass of CuSO45H2O.
CuSO45H2O's molar mass is equal to 249.68 g/mol moles. CuSO45H2O = 125.00 g x 249.68 g/mol x 0.501 mol
CuSO4 and 5H2O undergo a reaction, resulting in CuSO4.
Using the molar mass of CuSO4, we can now convert 0.501 moles of anhydrous copper (II) sulfate into grams:
79.91 g CuSO4 is equal to 0.501 mol CuSO4 times 159.609 g/mol.
What is copper(ii) sulfate pentahydrate?The most prevalent form of copper(II) sulfate hydrate is the pentahydrate (n = 5). The pentahydrate has also gone by the names blue vitriol, bluestone, copper vitriol, and Roman vitriol in the past. The most prevalent form of copper(II) sulfate is the vivid blue pentahydrate CuSO45H2O.
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PLEASE HELP ME GUYS!! I NEED THE CORRECT ANSWER! IF YOU ARE NOT SURE, PLEASE LET SOMEONE ELSE ANSWER! IT'S ONLY FIVE POINTS!
Question: What information can the atomic emission spectra of a distant star yield for scientists?
A. chemical composition of the star
B. age of the star
C. number of electrons in the star
D. distance to the star
Answer:
A. Chemical composition of the star
Explanation:
'Each element absorbs light at specific wavelengths unique to that atom. When astronomers look at an object's spectrum, they can determine its composition based on these wavelengths' - astronomy.com
'Atomic emission spectra are unique spectra of light emitted by an element when electricity is run through it or when it is viewed through a prism. Because they are unique, they can act as an element s fingerprint' - brightstorm.com
Answer:
The science of spectroscopy is quite sophisticated. From spectral lines astronomers can determine not only the element, but the temperature and density of that element in the star. The spectral line also can tell us about any magnetic field of the star. The width of the line can tell us how fast the material is moving.
