Chemistry - Stoichiometry

You have 20 g of a buckyball (C20). How many moles do you have?

0.08 mol

How many moles of nitrogen gas are in a 10.0 L container at STP?

0.45 moles

Which condition is STP?

0°C and 1 atm

Which amount has the greatest mass?

1 mole of uranium

For the oxidation of glucose (C6H12O6 + 6O2→6H2O + 6CO2), how many grams of oxygen gas will be consumed when 950 g of glucose is oxidized completely?

1,013g

A sample of nitrogen gas (N2) contains 1.2×10^24 atoms of nitrogen. About how many moles of nitrogen gas are in the sample?

1.0

You have 200 g of a substance with a molar mass of 150 g/mol. How many moles of the substance do you have?

1.33 mol

Approximately how many particles are in 3 moles?

1.8×10^24

What is the molar mass of calcium carbonate (CaCO3)?

100 g/mol

Consider this reaction:Li3N (s) + 3H2O (l)→NH3 (g) + 3LiOH (l)You need to make 24 g LiOH. How many grams of Li3N must you react with excess water?

11.7 g

You are asked to make 112 g of iron from iron oxide and excess carbon monoxide.Fe2O3(s) + 3CO(g)→2Fe(l) + 3CO2(g) Approximately how many grams of iron oxide is used?

160 g

What is the molar mass of ammonia (NH3)?

17 g/mol

What is the formula mass of calcium sulfate dihydrate [CaSO4⋅2H2O]? Be sure to add the water of hydration, which is the 2H2O part (water surrounding the calcium sulfate).

172 g/mol

What is the correct ratio of carbon to hydrogen to oxygen in glucose (C6H12O6) ?

1:2:1

Each molecule of hydrogen gas (H2) is made of two hydrogen atoms. You have 6.022 × 10^23 molecules of hydrogen gas. How many moles of hydrogen atoms do you have?

2

A reaction with a percent yield of 45% produces 900 g of product. What was the theoretical yield?

2,000 g

How many total atoms are in one mole of ammonia (NH3)?

2.4 × 10^24

You have 39 g of sodium azide in an air bag[2NaN3 (s)​ →2Na (s) + 3N2(g)]. How many liters of nitrogen will it make at STP?

20.2 L

You collect 44.8 L of ammonia in excess hydrogen(N = 14 amu, H = 1 amu). For the Haber process, N2 + 3H2→2NH3, what volume of nitrogen is consumed at STP?

22.4 L

What is one molar volume of the gas ammonia (NH3) at STP?

22.4 L/mol

A chemical reaction yields 1 mole of lithium hydroxide (LiOH). How many grams of lithium hydroxide are present?

24 g

For 2Na (s)​ + ​Cl2 (g)→2NaCl (s), how many grams of sodium chloride will be made from 115 g of sodium metal when reacted with excess chlorine gas?

293 g

Two molecules of one reactant combine with 3 molecules of another to produce 5 molecules of a product. Which equation is the correct representation of the reaction?

2A+3B→5C

For the reaction NH4NO3(s) →N2O(g) ​+​ 2H2O(l) , you decompose 60 g of NH4NO3 and get 11 g of N2O .What is the percent yield?

33%

What is the formula mass (molar mass) of sucrose (C12H22O11), table sugar?

342 g/mol

When ethane (C2H6) burns, it produces carbon dioxide and water: 2C2H6(g)+7O2(g)→4CO2(g)+6H2O(l)How many liters of carbon dioxide will be produced when 179 L of ethane are burned? (One mole of any gas occupies 22.4 L under certain conditions of temperature and pressure. Assume those conditions for this question.)

358 L

For the oxidation of glucose(C6H12O6 + 6O2→6H2O + 6CO2) , how many moles of oxygen will it take to consume 6 moles of glucose?

36

For the Haber process, N2 + 3H2→2NH3, which mole ratio is used to calculate the yield of ammonia when given hydrogen?

3:2

Ammonia (NH3) can be produced by the reaction of hydrogen gas with nitrogen gas:3H2 + N2→2NH3 A chemist reacts 2.00 mol H2 with excess N2. The reaction yields 0.54 mol NH3. What is the percent yield of the reaction?

40%

In a spacecraft, this reaction occurs:CO2(g)+2LiOH(s)→LiCO3(s)+H2O(l)How many liters of carbon dioxide will 4 moles of lithium hydroxide (LiOH) absorb? (One mole of any gas occupies 22.4 L under certain conditions of temperature and pressure. Assume those conditions for this question.)

45 L

When calcium carbonate is heated, it breaks down into calcium oxide and carbon dioxide.CaCO3(s) →CaO(s) + CO2(g)You heat 25 g CaCO3. Approximately what volume of carbon dioxide will you make? Assume the conditions of temperature and pressure are such that 1 mole of any gas will occupy 22.4 L.

5.6 L

What volume does 0.25 moles of oxygen gas occupy at STP?

5.60 L

When aluminum oxidizes in air, it forms aluminum oxide (Al2O3):4Al(s)+3O2(g)→2Al2O3(s) A 102 g sheet of aluminum oxide formed completely in excess oxygen. How many grams of aluminum were oxidized?

54 g

Consider this reaction: H2(g)+Cl2→2HCl(g) How many liters of HCl are produced when 28 L of chlorine are reacted with excess hydrogen? (One mole of any gas occupies 22.4 L under certain conditions of temperature and pressure. Assume those conditions for this question.)

56 L

When 90 g of water is split by electrolysis (2H2O →2H2 + O2) at STP, how many liters of oxygen gas will be collected?

56.0 L

Which value approximately represents the number of atoms in one mole of gold?

6.02 × 10^23

What is the volume of 3 moles of methane (CH4)? (One mole of any gas occupies 22.4 L under certain conditions of temperature and pressure. Assume those conditions for this question.)

67.2 L

Rasheed calculates that his chemical reaction should produce 4 moles of product, but when he does the experiment, he gets only 3 moles. What is his percent yield?

75%

When ethane (C2H6) burns, it produces carbon dioxide and water: 2C2H6(g)+7O2(g)→4CO2(g)+6H2O(l) How many moles of water will be produced when 3 moles of ethane are burned?

9 moles

Consider this hypothetical reaction: A+3B→C+3D. Assume that the equation is balanced. Which mole ratio will produce the most product?

A/3B

Consider this hypothetical reaction: A+3B→C+3D. Assume that the equation is balanced. In which reactant mole ratios will reactant B be the limiting reagent?

A/B

You have one mole of each of these atoms: carbon-12, oxygen-16, and uranium-235. Which substance has more atoms?

All have the same number of atoms.

Which compound has an element ratio of 1:2:6? Ba(NO3)2+ Na2SO4→BaSO4+2NaNO3

Ba(NO3)2

You have two containers at 25°C and 1 atm. One has 22.4 L of hydrogen gas, and the other has 22.4 L of oxygen gas. Which statement is true?

Both containers have the same number of molecules.

Which compound does not form a precipitate when reacted with sodium hydroxide?

NaNO3

Which statement is true about 22.4 L each of hydrogen, ammonia, and uranium dioxide gas assuming that the temperature and pressure are the same for all the gases?

The gases have the same number of molecules.

What would cause the percent yield of a reaction to be less than 100%?

The product participates in a side reaction.

The chemical standard for the quantity of a mole is based on which substance?

carbon-12

Which term is not a measure of the quantity of matter?

degrees Celsius

In viewing a chemical equation, how do you determine the ratios that relate reactants and products?

from the coefficients of the reactants and products

Which concept accounts for the whole-number subscripts in chemical formulas?

law of multiple proportions

What is the measure of the efficiency of a chemical reaction?

percent yield

You want to find the actual amount of reactants that are needed to get a desired amount of product. Which information is required?

percent yield

What is the branch of chemistry that examines numerical relationships in chemical reactions?

stoichiometry

What does the law of multiple proportions account for?

subscripts in chemical formulas