EQUATIONS and STOICHIOMETRY PRACTICE TEST

1. Consider the combustion of carbon monoxide with oxygen gas to produce carbon dioxide. Starting with 3.60 moles of carbon monoxide, calculate the grams of carbon dioxide produced. 2 CO + O2 → 2 CO2

a) 158b) 5.66c) 79.2d) 2.83

2. Silicon tetrachloride can be prepared by heating silicon in chlorine gas. How many moles of chlorine gas must be used to produce 201 g of silicon tetrachloride? The unbalanced reaction is as follows:

Si + Cl2 → SiCl4

a) 1.18b) 2.36c) 168d) 83.9

3. If you drop 12 moles of copper into a beaker containing nitric acid, how many moles of NO would be produced? 3 Cu + 8 HNO3 → 3 Cu(NO3)2 + 2 NO + 4 H2O

a) 2.0b) 4.0c) 8.0d) 12

4. How many liters of oxygen gas react completely with 1.2 L of hydrogen at STP? 2 H2 + O2 → 2 H2O

a) 1.2 Lb) 0.60 Lc) 2.4 Ld) 4.8 L

5. CaCO3 → CaO + CO2 If 50.0 g of CaCO3 react, how many liters of CO2 are produced at STP?

a) 1.14 Lb) 25.5 Lc) 11.2 Ld) 0.500 L

6. When the equation for the double replacement reaction below is balanced, what will be the coefficient for KCl? SnCl4 + K3PO4 → Sn3(PO4)4 + KCl

a) 3b) 4c) 6d) 12

7. The coefficients in a chemical equation represent the _____.

a) masses in grams of all reactants and products

b) relative number of moles of reactants and products

c) number of atoms of each element in each compound in a reaction

d) number of valence electrons involved in a reaction

8. In a chemical reaction, the mass of the products

a) is less than the mass of the reactantsb) is greater than the mass of the reactants

c) is equal to the mass of the reactantsd) has no relationship to the mass of the reactants

9. Calculate the moles of HNO3that are needed to neutralize 24.5 moles of Ca(OH)2.

2 HNO3 + Ca(OH)2 → Ca(NO3)2 + 2 H2O

a) 12.3 molb) 49.0 molc) 22.4 mold) 24.5 mol

Use pages 6 and 7 of the NCDPI Reference Tables for Chemistry where applicable.

10. tin + iron (II) sulfate → {HINT: Use tin (II)}

a) Sn + FeSO4 → SnSO4 + Feb) 2 Sn + Fe(SO4)2 → 2 SnSO4 + Fe

c) Sn + FeSO3 → SnSO3 + Fed) no reaction

11. silver nitrate + nickel (II) chloride → What is the net ionic equation?

a) Ni2+ + 2 NO31- → Ni(NO3)2

b) Ni + 2 NO3 → Ni(NO3)2

c) Ag1+ + Cl1- → AgCl

d) Ag + Cl → AgCl

12. zinc iodide + bromine →

a) ZnI + Br → ZnBr + Ib) 2 ZnI + Br2 → 2 ZnBr + I2

c) ZnI2 + Br2 → ZnBr2 + I2d) no reaction

13. chromium (III) selenide →

a) CrSe3 → Cr + 3 Seb) 2 CrSe3 → 2 Cr + 3 Se2

c) 2 Cr2Se3 → 4 Cr + 3 Se2d) Cr2Se3 → 2 Cr + 3 Se

14. calcium oxide + water →

a) CaO + H2O → H2CaO2b) Ca2O + H2O → Ca(OH)2

c) CaO + H2O → Ca(OH)2d) CaO + H2O → 2 CaOH

15. sulfur dioxide + water →

a) SO2 + H2O → H2SO4b) SO2 + H2O → H2SO3

c) S2O + H2O → 2 HSOd) S2O + H2O → H2SO3

16. tin + oxygen gas → {HINT: Use tin (II)}

a) 2 Sn + O2 → 2 SnOb) Sn + O2 → SnO2

c) Sn + O → SnOd) Sn + 2 O → SnO2

17. mercury (II) chlorate →

a) 2 HgClO3 → HgCl2 + 3 O2b) 2 HgClO3 → 2 HgCl + 3 O2

c) Hg(ClO3)2 → HgCl + 3 O2d) Hg(ClO3)2 → HgCl2 + 3 O2

18. gold (I) carbonate →

a) Au2CO3 → Au2O + CO2b) Au2CO3 → AuO + CO2

c) Au2(CO3)3 → 2 AuO + 3 CO2d) Au2(CO3)3 → Au2O3 + 3 CO2

19. sodium sulfate + barium nitrate → Predict the products. What is formula for the precipitate formed?

a) BaSO4 b) NaNO3c) Ba2(SO4)2d) Na(NO3)2

20. sodium + water (cold) →

a) Na + H2O → NaOH + 2 Hb) 2 Na + H2O → Na2O + H2

c) 2 Na + 2 H2O → 2 NaOH + H2d) no reaction

Classify the following unbalanced reactions. Choose (a) for synthesis, (b) for decomposition,

(c) for single-replacement, (d) for double-replacement, and (e) for combustion.

___ 21. H3PO3 → P2O3 + H2O___ 22. Li + Fe(C2H3O2)3 → LiC2H3O2 + Fe

___ 23. Al + H2 → AlH3___ 24. Sn(ClO3)2 → SnCl2 + O2

___ 25. Ag2CO3 → Ag2O + CO2___ 26. C5H8 + O2 → CO2 + H2O

___ 27. HBr + NH4OH → NH4Br + H2O___ 28. BaO + H2O → Ba(OH)2

29. The equation A + BX → AX + B is the general equation for a _____ reaction.

a) double-replacementb) decompositionc) single-replacementd) combustion

Equations and Stoichiometry Practice Test - page 1