Answer to Question #347617 in General Chemistry for Toniece

Question

Question 9

Calculate the number of moles of NH₃ present in 100 g of NH₃

a. 0.170 mol

b. 5.87 mol

c. 17.0 mol

d. 100 mol

e. 1703 mol

Question 10

Calculate the mass percentage of hydrogen in methane, CH₄

a. 0.062 %

b. 0.251 %

c. 6.28 %

d. 12.6 %

e. 25.1 %

 Question 11

A compound which contains 0.0130 mol C, 0.390 mol H and 0.065 mol O. What is the empirical formula for this compound?

a. CHO

b. CH₅O₂

c. CH₃₀O₅

d. CH₃₉O₆

e. C₂H₆₀O₁₀

Question 12

What is the empirical formula for a compound that contains 17.34 % hydrogen and 82.66 % carbon by mass?

a. CH

b. CH₂

c. CH₃

d. C₂H₅

e. C₅H

 Question 13

Consider the following information to answer questions 13-17 below:

The unbalanced reaction of magnesium with oxygen is:

Mg + O₂ → MgO

 The correct balanced reaction is:

a. Mg₂ + O₂ → 2MgO

b. 2Mg + ½ O₂ → Mg₂O

c. 2Mg + O₂ → 2MgO  

d. Mg + O₂ → MgO₂

e. None of the above

Answer 1

1)a

2)e

3)e

4)c

5)c