Chemistry

How many moles of aluminum are needed to react completely with 1.2 mol of FeO? 2Al(s) + 3FeO(s) ® 3Fe(s) + Al2O3 2.4 mol 1.2 mol 0.8 mol 1.6 mol

.8 mol

Calculate the number of moles of Al2O3 that are produced when 0.60 mol of Fe is produced in the following reaction. 2Al(s) + 3FeO(s) -> 3Fe(s) + Al2O3(s) 0.60 mol 0.20 mol 0.90 mol 0.40 mol

0.20 mol

How many liters of chlorine gas can be produced when 0.98 L of HCl react with excess O2 at STP? 4HCL(g)+O2(g) yields 2Cl2(g)+2H2O(g) 3.9 L 0.98 L 2.0 L 0.49 L

0.49 L

Which conversion factor do you use first to calculate the number of grams of CO2 produced by the reaction of 50.6 g of CH4 with O2? The equation for the complete combustion of methane is: CH4(g) + 2O2(g) yields CO2(g)_2H2O(l) 44.0g CO2/2 mol CO2 1 mol CH4/16.0 g CH4 16.0 g CH4/1 mol CO4 2 mol O2/1 mol CO2

1 mol CH4/16.0 g CH4

Which of the following statements about the reaction below is true ? 3NaHCO3(aq) + C6H8O7 (aq) yields 3CO2(g) + 3H2O(s) + Na3C6H5O7(aq) 22.4 L of CO2 (g) are produced for every liter of C6H8O7(aq) reacted. 1 mole of water is produced for every mole of carbon dioxide produced. 6.02x10^23 molecules of Na3C6H5O7(aq) are produced for every mole of NaHCO3(aq) used. 54 g of water are produced for every mole of NaHCO3(aq) are produced.

1 mole of water is produced for every mole of carbon dioxide produced.

How many moles of H3PO4 are produced when 71.0 g P4O10 reacts completely to from H3PO4? P4O10(s)+6H2O(l) yields 4H3PO4(aq) 16.0 mol 4.00 mol 1.00 mol 0.063 5 mol

1.00 mol

At STP, how many liters of oxygen are required to react completely with 3.6 liters of hydrogen to form water? 2H2(g)+O2(g) yields 2H2O(g) 2.0 L 1.8 L 3.6 L 2.4 L

1.8 l

When iron rusts in air, iron(III) oxide is produced. How many moles of oxygen react with 2.4 mol of iron in the rusting reaction? 4Fe(s)+3O2(g) yields 2Fe2O3(s) 1.8 mol 3.2 mol 2.4 mol 1.2 mol

1.8 mol

How many liters of hydrogen gas are needed to react with CS2 to produce 2.50 L of CH4 at STP? 4H2(g)+CS2(l) yields CH4(g)+2H2S(g) 10.0 L 7.50 L 5.00 L 2.50 L

10.0 L

Mercury can be obtained by reacting mercury(II) sulfide with calcium oxide. How many grams of calcium oxide are needed to produce 36.0 g of Hg? 4HgS(s) + 4CaO(s) yields 4Hg(l) + 3CaS(s) + CaSO4 1.80 g 7.56 g 13.4 g 10.1 g

10.1 g

Metallic copper is formed when aluminum reacts with copper(II) sulfate. How many grams of metallic copper can be obtained when 54.0 g of Al react with 319 g of CuSO4 ? Al + 3CuSO4--> Al2 (SO4 )3+ 3Cu 162 g 381 g 127 g 21.2 g

127 g

How many grams of chromium are needed to react with an excess of CuSO4 to produce 27.0g Cu? 2Cr(s) + 3CuSO4(aq)---->Cr2(SO4)3(aq) + 3Cu(s) 33.2 g 18.0 g 14.7 g 81.5 g

14.7 g

In the reaction 2CO(g) + O2(g) ® 2CO2(g), what is the ratio of moles of oxygen used to moles of CO2? 2:1 1:2 1:1 2:2

1:2

Which of the following is an INCORRECT interpretation of the balanced equation shown below? 2S(s) + 3O2(g) --->2SO3(g) 2 atoms S + 3 molecules O2 ® 2 molecules SO3 2 mol S + 3 mol O2 ® 2 mol SO3 5 mol of reactants ® 2 mol of products

2 g S + 3 g O2--> 2 g SO3

Hydrogen gas can be produced by reacting aluminum with sulfuric acid. How many moles of sulfuric acid are needed to completely react with 15.0 mol of aluminum? 2Al(s) + 3H2SO4(aq) yields Al2(SO4)3(aq) + 3H2(g) 10.0 mol 22.5 mol 0.100 mol 15.0 mol

22.5 mol

Iron(III) oxide is formed when iron combines with oxygen in the air. How many grams of Fe2O3 are formed when 16.7 g of Fe reacts complete with oxygen? 4Fe(s)+3O2(g) yields 2Fe2O3(s) 47.8 g 23.9 g 12.0 g 95.6 g

23.9g

Aluminum reacts with sulfuric acid to produce aluminum sulfate and hydrogen gas. How many grams of aluminum sulfate would be formed if 250 g H2SO4 completely reacted with aluminum? 2Al(S)+3H2SO4(aq) yields Al2(SO4)3(aq)+3H2(g) 290 g 0.85 g 870 g 450 g

290 g

If 1 egg and 1/3 cup of oil are needed for each bag of brownie mix, how many bags of brownie mix do you need if you want to use up all 3 eggs and 1 cup of oil? 3 4 1 2

3

Methane and hydrogen sulfide form when hydrogen reacts with carbon disulfide. Identify the excess reagent and calculate how much remains after 36 L of H2 with 12 L of CS2. 4H2(g) + CS2(g) -> CH4(g) + 2H2S(g) 3 L CS2 9 L CS2 6 L CS2 12 L H2

3 L CS2

Hydrogen gas is produced when zinc reacts with hydrochloric acid. If the actual yield of this reaction is 85%? how many grams of zinc are needed to produce 112 l of H2 at STP? 180 g 95 g 280 g 380 g

380g

What is the maximum number of grams of PH3 that can be formed when 6.2g of phosphorus reacts with 4.0 g of hydrogen to form PH3? P4(g) +6H2(g) yields 4PH3(g) 270 g 6.8 g 45 g 0.43 g

6.8 g

How many grams of H3PO4 are produced when 10.0 moles of water react with an excess of P4O10? P4O10(s)+6H2O(l) yields 4H3PO4(aq) 147 g 6.7 g 653 g 1.22 g

653 g

When glucose is consumed, it reacts with oxygen in the body to produce carbon dioxide, water, and energy. How many grams of carbon dioxide would be produced if 45 g of C6H12O6 completely reacted with oxygen? 11 g 66 g 1.8 g 1.5 g

66 g

Calcium oxide, or lime, is produced by the thermal decomposition of limestone in the reaction CaCO3(s) yields Cao(s) + CO2(g). What mass of lime can be produced from 1.5x10^3 kg of limestone? 8.4x10^2kg 8.4 kg 8.4x10^5kg none of the above

8.4x10^2kg

Lead nitrate can be decomposed by heating. What is the percent yield of the decomposition reaction if 9.9 g Pb(NO3 )2 are heated to give 5.5 g of PbO? 2Pb(NO3 )2(s) -->2PbO(s) + 4NO2(g) + O2 (g) 44% 67% 56% 82%

82%

In a particular reaction between copper metal and silver nitrate, 12.7 g Cu produced 38.1 g Ag. What is the percent yield of silver in this reaction? Cu+2AgNO3 yields Cu(NO3)2 + 2Ag 176% 56.7% 88.2% 77.3%

88.2%

Which of the following is true about the reaction shown below? C5H12(l)+8O2(g) yields 5CO2(g)+6H2O(g) 9 atoms of reactants chemically change into 11 atoms of product. 9 grams of reactants chemically change into 11 grams of product. 9 liters of reactants chemically change into 11 liters of product. 9 moles of reactants chemically change into 11 moles of product.

9 moles of reactants chemically change into 11 moles of product.

Glucose, C6H12O6, is a good source of food energy. When it reacts with oxygen, carbon dioxide and water are formed. How many liters of CO2 are produced when 126 g of glucose completely react with oxygen? C6H12O6(s)+6O2(g) yields 6CO2(g) + 6H2O(l) + 673 kcal 4.21 L 5.33 L 15.7 L 94.1 L

94.1 L

the amount of product formed when a reaction is carried out in the laboratory

Actual yield

Which of the following is NOT a reason why actual yield is less than theoretical yield? conservation of mass competing side reactions impure reactants present loss of product during purification

Conservation of mass

In a chemical reaction, the mass of the products is equal to the mass of the reactants. is less than the mass of the reactants. is greater than the mass of the reactants. has no relationship to the mass of the reactants.

Is equal to the mass of the reactants

This is conserved in every ordinary chemical reaction.

Mass

Which of the following are conserved in every chemical reaction? moles and molecules mass and molecules mass and atoms moles and liters

Mass and atoms

What is conserved in the reaction shown below? N2(g) + 3F2(g) yields 2NF3(g) moles only atoms only mass and atoms only mass only

Mass and atoms only

In any chemical reaction, what quantities are always preserved? the number of moles and the volumes the number of molecules and the volumes mass and number of atoms mass and moles

Mass and number of atoms

What is conserved in the reaction shown below? H2(g) + Cl2 (g) yields 2HCl(g) mass only mass and moles only mass, moles, molecules, and volume mass, moles, and molecules only

Mass, moles, molecules, and volume.

This quantity can always be used in the same way as moles when interpreting balanced chemical equations

Number of molecules

Identify the limiting reagent and the volume of CO2 formed when 11 L CS2 reacts with 18 L O2 to produce CO2 gas and SO2 gas at STP. CS2(g) + 3O2(g) yields CO2(g) + 2SO2 (g) O2; 27 L CO2 O2; 6.0 L CO2 CS2; 11 L CO2 CS2; 5.5 L CO2

O2; 6.0 L CO2

the ratio of the actual yield to the theoretical yield

Percent yield

Which of the following is true about "yield"? The actual yield may be different from the theoretical yield because insufficient limiting reagent was used. The percent yield may be different from the theoretical yield because reactions do not always go to completion. The value of the actual yield must be given in order for the percent yield to be calculated. The theoretical yield is always the same as the actual yield.

The actual yield may be different from the theoretical yield because insufficient limiting reagent was used.

The limiting reagent is Fe2O3 and 24 mol Fe will be formed. The limiting reagent is CO and 3.0 mol CO2 will be formed. The limiting reagent is CO and 8.0 mol Fe will be formed. The limiting reagent is Fe2O3 and 36 mol CO2 will be formed.

The limiting reagent is CO and 8.0 mol Fe will be formed.

When 0.1 mol of calcium reacts with 880 g of water, 2.24 L of hydrogen gas form (at STP). How would the amount of hydrogen produced change if the volume of water was decreased to 440 mL (440 g)? No hydrogen would be produced. Only one half the volume of hydrogen would be produced. The volume of hydrogen produced would double. The volume of hydrogen produced would be the same.

The volume of hydrogen produced would be the same.

When an equation is used to calculate the amount of product that will form during a reaction, then the value obtained is called the ____. theoretical yield actual yield minimum yield percent yield

Theoretical yield

the maximum amount of product that could be formed from given amounts of reactants

Theoretical yield

This is conserved only in reactions where the temperature is constant and the number of moles of gaseous reactants is the same as that of gaseous products.

Volume

Which type of stoichiometric calculation does not require the use of the molar mass? mass-mass problems mass-volume problems volume-volume problems mass-particle problems

Volume-volume problems

What is the first step in most stoichiometry problems? convert given quantities to masses convert given quantities to moles convert given quantities to volumes add the coefficients of the reagents

convert given quantities to moles

the reactant that is not completely used up in a reaction

excess reagent

When two substances react to form products, the reactant which is used up is called the ____. excess reagent limiting reagent determining reagent catalytic reagent

limiting reagent

the reactant that determines the amount of product that can be formed in a reaction

limiting reagent

The calculation of quantities in chemical equations is called ____. percent yield stoichiometry percent composition dimensional analysis

stoichiometry