#### Question

# Stoichiometry Conversions (HELP)! :(?

i have a final due tomorrow which i need to pass in order to pass the class; problem is i dont get the material at all; & i've tried but i cant figure it out; i also have a horrible teacher who just SUCKS at teaching in my opinion. if anyone out there can help me, ill GREATLY appreciate it . plz & thank you.

1) Which coefficients correctly balance the formula NH4NO2 → N2 + H2O?

A.1,2,2

B.1,1,2

C.2,1,1

D.2,2,2

2) Given the equation 3A + 2B → 2C, the starting mass of A, and its molar mass, and you are asked to determine the moles of C produced, your first step in solving the problem is the multiply the given mass of A by:

A. 2 mol C

-----------

3 mol A

B. 3 mol A

-----------

2 mol C

C. 1 mol A

-------------------

molar mass A

D. molar mass A

---------------------

1 mol A

3) In the chemical reaction represented by the equation wA + xB → yC + zD, a comparison of the numbers of moles of A to the number of moles of C would be a(n)

A.mass ratio

B.mole ratio

C.electron ratio

D.energy proportion

4) In the reaction represented by the equation C + 2H2- → CH4, what is the mole ratio of hydrogen to methane?

A.1:1

B.2:1

C.1:2

D.2:4

5) The haber process for producing ammonia commercially is represented by the equation N2(g) + 3H2(g) → 2NH3(g). To completely convert 9.0 mol hydrogen gas to ammonia gas, how many moles of nitrogen gas are required?

A.1.0 mol

B.2.0 mol

C.3.0 mol

D.6.0 mol

6) In the equation 2KCIO3 → 2KCI + 3O2, how many moles of oxygen are produced when 3.0 mol of KCIO3 decompose completely?

A.1.0 mol

B.2.5 mol

C.3.0 mol

D.4.5 mol

7) For the reaction represented by the equation 2H2 + O2→ 2H2O, how many moles of water can be produced from 6.0 mol of oxygen?

A.2.0 mol

B.6.0 mol

C.12 mol

D.18 mol

8) For the reaction represented by the equation 2H2- + O2 → 2H2O, how many grams of water are produced from 6.00 mol of hydrogen?

A.2.00 g

B.6.00 g

C.54.0 g

D.108 g

9) For the reaction represented by the equation 2Na + 2H2O → 2NaOH + H2, how many grams of sodium hydroxide are produced from 3.0 mol of sodium with an excess of water?

A. 40.g

B. 80.g

C. 120 g

D. 240 g

10) For the reaction represented by the equation 2Na + CI2 → 2NaCI, how many grams of chlorine gas are required to react completely with 2.00 mol of sodium?

A.35.5 g

B.70.9 g

C.141.8 g

D.212.7 g

11) For the reaction represented by the equation CH4 + 2O2 → CO2 + 2H2O, how many moles of carbon dioxide are produced from the combustion of 100. g of methane?

A.6.23 mol

B.10.8 mol

C.12.5 mol

D.25 mol

12) For the reaction represented by the equation Pb(NO3)2 + 2KI → PbI2 + 2KNO3, how many moles of lead (II) iodide are produced from 300. g of potassium iodide and an excess of Pb(NO3)2 ?

A.0.904 mol

B.1.81 mol

C.3.61 mol

D.11.0 mol

13) For the reaction represented by the equation 3Fe + 4H2O → Fe3O4 + 4H2, how many moles of iron (III) oxide are produced from 500. g of iron in an excess of H2O?

A.1.04 mol

B.2.98 mol

C.8.95 mol

D.12.98 mol

14) For the reaction represented by the equation 2KIO3 → 2KCI + 3O2, how many moles of potassium chlorate are required to produce 250. g of oxygen?

A.2.00 mol

B.4.32 mol

C.4.97 mol

D.5.21 mol

15) For the reaction represented by the equation of 2Na + 2H2O → 2NaOH + H2, how many grams of hydrogen are produced if 120. g of sodium and 80. g of water are available?

A.4.5 g

B.45 g

C.80. g

D.200 g

#### Answers

1) Which coefficients correctly balance the formula NH4NO2 → N2 + H2O?

BCE: NH4NO2 = N2 + 2 H2O

ANS: B

2) Given the equation 3A + 2B → 2C, the starting mass of A, and its molar mass, and you are asked to determine the moles of C produced, your first step in solving the problem is the multiply the given mass of A by:

step: given g of A x(mol A/ g of A) x(mol C/ mol A)= mol C

ANS: C

take your time and do the rest it'll be beneficial for your final...practice make perfect...good luck

B.CHEMIST