Question

41)

Combustion analysis of a 0.675 g sample of an unknown compound that contains only carbon, hydrogen, and oxygen gives 0.627 g of CO₂ and 1.534 g of H₂O. The molecular mass of the unknown is

Select one:

A. C₆H₁₂O₂.

B. C₃H₆O.

C. C₉H₁₈O₃.

D. unable to be determined from this data.

42)

How many milliliters of 0.550 M hydriodic acid are needed to react with 25.00 mL of 0.217 M CsOH?
HI(aq) + CsOH(aq) → CsI(aq) + H₂O(l)

Select one:

A. 0.0158 mL

B. 9.86 mL

C. 63.4 mL

D. 0.101 mL

43)

How many moles of BCl₃ are needed to produce 25.0 g of HCl(aq) in the following reaction?
BCl₃(g) + 3 H₂O(l) → 3 HCl(aq) + B(OH)₃(aq)

Select one:

A. 0.229 mol

B. 2.06 mol

C. 0.686 mol

D. 4.38 mol

44)

Combustion analysis of an unknown compound containing only carbon and hydrogen produced 4.554 g of CO₂ and 2.322 g of H₂O. What is the empirical formula of the compound?

Select one:

A. C₅H₂

B. CH₂

C. C₂H₅

D. C₄H₁₀

₄₅₎

What is the mass of 8.50 × 10²² molecules of NH₃?

Select one:

A. 2.40 g

B. 0.00830 g

C. 0.417 g

D. 120 g

Answer 1