CHM101 Quiz - Xirius

1. What is the mole relationship between KClO3 decomposed and O2 produced according to the balanced equation 2KClO3 → 2KCl + 3O2?

A. 1 mol KClO3 produces 1 mol O2 B. 2 mol KClO3 produces 3 mol O2 C. 3 mol KClO3 produces 2 mol O2 D. 1 mol KClO3 produces 2 mol O2

2. In the reaction CaO + SO2 → CaSO4, what is the mole ratio of CaO to SO2?

A. 2:1 B. 1:2 C. 1:1 D. 3:2

3. Calculate moles of sulfur dioxide in 1400 L at STP.

A. 31.25 mol B. 62.5 mol C. 70.0 mol D. 50.0 mol

4. The balanced decomposition reaction of ammonium dichromate \((NH_4)_2Cr_2O_7\) is:

A. \((NH_4)_2Cr_2O_7 \rightarrow N_2 + 4H_2O + Cr_2O_3\) B. \((NH_4)_2Cr_2O_7 \rightarrow NH_3 + H_2O + Cr_2O_3\) C. \((NH_4)_2Cr_2O_7 \rightarrow N_2 + H_2 + Cr_2O_3\) D. \((NH_4)_2Cr_2O_7 \rightarrow N_2 + H_2O + Cr\)

5. How many moles are there in 5.150 grams of \(KClO_3\) (molar mass 122.5 g/mol)?

A. 0.04204 mol B. 0.0500 mol C. 0.0300 mol D. 0.0625 mol

6. How many grams of Cr2O3 are produced from the decomposition of 0.84 g of ammonium dichromate?

A. 0.25 g B. 0.50 g C. 0.51 g D. 0.84 g

7. In the decomposition of sodium bicarbonate (NaHCO3), what is the mole ratio of NaHCO3 to Na2CO3 formed?

A. 1:2 B. 2:1 C. 1:1 D. 3:1

8. When 16.8 g of NaHCO3 is heated completely, how many grams of sodium carbonate (Na2CO3) are produced?

A. 5.3 g B. 8.4 g C. 10.6 g D. 16.8 g

9. Calculate the volume of \(CO_2\) produced when 10 mL of ethane is burnt.

A. 10 mL B. 15 mL C. 20 mL D. 25 mL

10. Given 50 mL supplied of \(O_2\) for ethane combustion, and 35 mL required, how much \(O_2\) is in excess?

A. 10 mL B. 15 mL C. 20 mL D. 35 mL

11. For the decomposition reaction of ammonium dichromate, what is the molar mass of (NH4)2Cr2O7?

A. 142.0 g/mol B. 252.0 g/mol C. 152.0 g/mol D. 106.0 g/mol

12. What is the balanced chemical equation for the reaction of phosphorus with oxygen producing diphosphorus pentoxide (P2O5)?

A. P4 + 3O2 → 2P2O5 B. 2P4 + 5O2 → 4P2O5 C. P4 + 5O2 → 2P2O5 D. P4 + O2 → P2O5

13. In the reaction \(2Al + 3H_2SO_4 \rightarrow Al_2(SO_4)_3 + 3H_2\), how many moles of \(H_2\) are produced from 2 moles of Al?

A. 2 moles B. 3 moles C. 4 moles D. 6 moles

14. How many grams of \(Na_2CO_3\) are produced from 16.8 g of \(NaHCO_3\)?

A. 8.4 g B. 10.6 g C. 16.8 g D. 20.0 g

15. What is the volume of hydrogen gas produced at STP from 0.0741 mol of Al reacting with sulfuric acid?

A. 1.65 L B. 2.49 L C. 3.31 L D. 4.12 L

16. In the thermal decomposition of potassium chlorate (KClO3), how many moles of O2 are produced from 2 moles of KClO3?

A. 1 mole B. 2 moles C. 3 moles D. 4 moles

17. What is the molar volume of a gas at standard temperature and pressure (STP)?

A. 18.0 L/mol B. 22.4 L/mol C. 44.0 L/mol D. 100.0 L/mol

18. What is the mass of calcium oxide required to react completely with 1.4 × 10³ L of \(SO_2\)?

A. 1.40 kg B. 2.50 kg C. 3.50 kg D. 4.00 kg

19. Calculate the molar mass of \( (NH_4)_2Cr_2O_7 \).

A. 252.0 g/mol B. 142.0 g/mol C. 106.0 g/mol D. 152.0 g/mol

20. The molar mass of aluminum (Al) is:

A. 27.0 g/mol B. 26.0 g/mol C. 28.0 g/mol D. 24.0 g/mol

21. Given the balanced reaction \(2KClO_3 \rightarrow 2KCl + 3O_2\), how many moles of \(O_2\) are produced from 2 moles of \(KClO_3\)?

A. 2 moles B. 3 moles C. 4 moles D. 6 moles

22. From the combustion of ethane, burning 10 mL of \(C_2H_6\) requires how many mL of \(O_2\)?

A. 20 mL B. 25 mL C. 35 mL D. 50 mL

23. The balanced equation for the reaction of phosphorus with oxygen to form diphosphorus pentoxide is:

A. \(P_4 + 5O_2 \rightarrow 2P_2O_5\) B. \(P_4 + 6O_2 \rightarrow 4P_2O_5\) C. \(2P_4 + 5O_2 \rightarrow P_2O_5\) D. \(4P + 5O_2 \rightarrow P_2O_5\)

24. In the reaction between aluminum and sulfuric acid producing aluminum sulfate and hydrogen gas, what is the mole ratio of aluminum to hydrogen gas?

A. 2:3 B. 3:2 C. 1:1 D. 3:1

25. The molar mass of calcium oxide (CaO) is:

A. 40.0 g/mol B. 56.0 g/mol C. 36.0 g/mol D. 48.0 g/mol

26. When ammonium dichromate ((NH4)2Cr2O7) decomposes, what is the mole ratio between ammonium dichromate and chromium (III) oxide (Cr2O3) formed?

A. 1:2 B. 2:1 C. 1:1 D. 3:2

27. According to the balanced equation 2Al + 3H2SO4 → Al2(SO4)3 + 3H2, what volume of hydrogen gas is produced at STP by 2.00 g of aluminum?

A. About 1.5 L B. About 2.5 L C. About 4.0 L D. About 5.0 L

28. What is the molar mass of sodium carbonate, \(Na_2CO_3\)?

A. 106.0 g/mol B. 84.0 g/mol C. 122.0 g/mol D. 60.0 g/mol

29. What is the molar mass of sodium bicarbonate \(NaHCO_3\)?

A. 106.0 g/mol B. 84.0 g/mol C. 122.0 g/mol D. 44.0 g/mol

30. How many liters of oxygen gas at STP are needed to produce 75.0 g of P2O5?

A. About 15 L B. About 22 L C. About 30 L D. About 45 L

31. Which step is necessary to convert mass of a reactant to volume of gas product at STP in stoichiometry problems?

A. Convert mass to moles, use mole ratio, then multiply by 22.4 L/mol B. Directly multiply mass by 22.4 L/mol C. Use volume ratios directly without moles D. Use molar volume of solids

32. What is the correct molar mass of calcium oxide (CaO)?

A. 40.0 g/mol B. 56.0 g/mol C. 16.0 g/mol D. 111.0 g/mol

33. How many liters of \(O_2\) gas at STP are required to produce 75.0 g of \(P_2O_5\)?

A. 22.4 L B. 29.6 L C. 35.0 L D. 40.0 L

34. When 10.0 grams of CaCO3 reacts completely with HCl, what is the mole ratio of CaCO3 to CO2 produced?

A. 2:1 B. 1:2 C. 1:1 D. 3:2

35. If 5.150 g of KClO3 decomposes completely, how many liters of oxygen gas (O2) can be collected at STP?

A. About 1.4 L B. About 2.0 L C. About 3.5 L D. About 5.2 L

36. Which gas is produced by the decomposition of potassium chlorate, \(KClO_3\)?

A. \(CO_2\) B. \(O_2\) C. \(H_2\) D. \(N_2\)

37. What volume does 1 mole of gas occupy at STP conditions?

A. 11.2 L B. 22.4 L C. 44.8 L D. 18.0 L

38. Calculate the molar mass of diphosphorus pentoxide, \(P_2O_5\).

A. 142.0 g/mol B. 152.0 g/mol C. 122.5 g/mol D. 106.0 g/mol

39. How do you calculate the mass of CaO needed to react with a given volume of SO2 at STP?

A. Convert volume of SO2 to moles, then use 1:1 mole ratio to CaO, finally multiply by molar mass of CaO B. Directly multiply volume of SO2 by molar mass of CaO C. Use molar volume of CaO to convert volume to mass D. Multiply volume of SO2 by volume of CaO

40. Which volume ratio of \(O_2\) to ethane (\(C_2H_6\)) is correct from the combustion reaction \(2C_2H_6 + 7O_2 \rightarrow 4CO_2 + 6H_2O\)?

A. 2:7 B. 7:2 C. 4:6 D. 2:4

41. What is the molar mass of chromium(III) oxide, \(Cr_2O_3\)?

A. 152.0 g/mol B. 142.0 g/mol C. 122.5 g/mol D. 106.0 g/mol

42. Which of the following is a correct method to calculate the amount of oxygen required to produce a given mass of P2O5 at STP?

A. Use mass directly to calculate volume of O2 B. Convert mass of P2O5 to moles, use mole ratio from balanced equation, then calculate volume of O2 using molar volume C. Use volume ratios directly between P4 and O2 D. Calculate volume of O2 from P4 only

43. If 0.84 g of ammonium dichromate decomposes, how many grams of \(Cr_2O_3\) are formed?

A. 0.506 g B. 0.748 g C. 0.400 g D. 0.650 g

44. Using the stoichiometric volume ratios, how much oxygen is required to completely burn 10 mL of ethane?

A. 10 mL B. 20 mL C. 35 mL D. 50 mL

45. Upon strong heating, 2 moles of \(NaHCO_3\) decompose to produce how many moles of \(Na_2CO_3\)?