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| 1 | |
Why is a balanced chemical equation needed to perform a stoichiometric calculation? |
| | A) | It tells you what reactants you need to mix together. |
| | B) | It tells you the physical state of the reactants. |
| | C) | The coefficients tell you the molar proportions of reactants to use. |
| | D) | The coefficients tell you what mass of reactants to use. |
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| 2 | |
What is true about the following reaction?
H2(g) + 1/2O2(g) →H2O(g) |
| | A) | There is the same number of particles on each side of the equation. |
| | B) | There is the same number of moles on each side of the equation. |
| | C) | Both sides of the equation represent mixtures. |
| | D) | There is the same number of each type of atom on each side of the equation. |
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| 3 | |
Which of the following relationships is not true according to the reaction below:
SiO2(s) + 4 HF(g) → SiF4(g) + 2 H2O (g) |
| | A) | 4 mol of HF are produced in reacting 1 mol of SiF4 |
| | B) | 1 mol of SiO2 produces 1 mol of SiF4 |
| | C) | 2 mol of H2O are produced from 4 mol of HF |
| | D) | 2 molecules of H2O are formed when 1 molecule of SiO2 isreacted. |
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| 4 | |
How many moles of nitrogen gas are produced from 0.513 mol of sodium azide in the following reaction:
2 NaN3 (s) → 3 N2(g) + 2 Na(s) |
| | A) | 0.342 mol |
| | B) | 0.513 mol |
| | C) | 0.770 mol |
| | D) | There is not enough information given to answer the question. |
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| 5 | |
Iron combines with molecular oxygen to form different oxides. What are the coefficients for iron, oxygen and iron(III) oxide in the balanced chemical equation for the formation of the oxide? |
| | A) | 2, 1, 3 |
| | B) | 4, 3, 2 |
| | C) | 6, 1, 2 |
| | D) | 2, 3, 2 |
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| 6 | |
In a balanced chemical equation |
| | A) | the mass of all of the reactants is equal to the mass of all the products. |
| | B) | there is the same number of each type of atom on each side of the equation. |
| | C) | atoms are not created or destroyed during the reaction but are simply arranged in different combinations. |
| | D) | all of the above. |
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| 7 | |
In performing a stoichiometric calculation what is the most important quantity to know or calculate concerning the substance for which you are given information? |
| | A) | The number of moles of that substance. |
| | B) | The molar mass of that substance. |
| | C) | The molar volume of that substance. |
| | D) | The mass of that substance. |
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| 8 | |
What is the first step in performing a stoichiometric calculation? |
| | A) | Determine the molar ratio between the required compound and the given compound. |
| | B) | Write a balanced chemical equation of the reaction. |
| | C) | Convert the mass, volume or number of particles of the given substance to the number of moles. |
| | D) | Convert the moles of the required substance to mass, volume or number of particles if necessary. |
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| 9 | |
What mass of metallic copper is produced when 0.280 mol of copper(II) chloride is reacted with Al in the following reaction:
3 CuCl2(aq) + 2 Al(s) → 2 AlCl3(aq) + 2 Cu(s) |
| | A) | 63.55 g |
| | B) | 53.4 g |
| | C) | 35.6 g |
| | D) | 17.8 g |
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