Stoichiometry Chapter 3 Grade 12 SABIS

Poll

What is the best place to go on vacation?

• Ocean

• Mountains

• Lake

• Amusement Park

• A foreign country

Poll

Would you rather read the book or watch the movie?

• Book

• Movie

Multiple Choice

2 KClO₃ → 2 KCl + 3 O₂
How many moles of oxygen are produced when 6.7 moles of KClO₃ decompose completely?

• 6.7 mol
• 1.0 mol
• 10.1 mol
• 4.5 mol

Poll

Should pineapple ever be put onto a pizza?

• Yes

• No

• I don't know.

• What is pineapple?

Poll

DC or Marvel?

• DC

• Marvel

• Both

• I have no clue what this means.

Multiple Choice

What is the percent yield of the following reaction if 145g of P₂O₅ reacts with 40 grams of water, but you only collect 112 grams of phosphoric acid?

3 H₂O + P₂O₅ -> 2H₃PO₄

• 80%

• 85%

• 77%

• 58%

Poll

Which of the following is the best candy bar?

• Snickers

• Milky Way

• Kit Kat

• Other

• I don't like candy bars.

Multiple Choice

Fe + S --> FeS
If 7.62g Fe react with 8.67g S, what is the limiting reactant?

• Fe
• S
• FeS
• none 

Multiple Choice

⁶³Cu is 69% of the naturally occurring isotope of Cu.  If only one other isotope is present for natural copper, what is it?

• ⁵⁹Cu
• ⁶⁵Cu
• ⁶¹Cu
• ⁶²Cu

Poll

Who is the best character from Toy Story?

• Buzz

• Woody

• Mr. Potatohead

• What is Toy Story?

Multiple Choice

What is the empirical formula if you have 81.82% carbon and 18.18% hydrogen?

• C3H8
• CH4
• C2H2
• C4H10

Poll

What is the best pet to have?

• Dog

• Cat

• Other

• I don't do pets.

Multiple Choice

When does a chemical reaction stop?

• When the lab is finished
• When the excess reactant is used up
• When the limiting reactant is used up
• Chemical reactions never stop

Multiple Choice

A 15.67 g sample of a hydrate of magnesium carbonate was heated to drive off the water. The mass was reduced to 7.58 g. What is the formula of the hydrate?

• MgCO₃ · 5H₂O
• MgCO₃ · 4H₂O
• MgCO₃ · 6H₂O
• MgCO₃ · 1H₂O

Multiple Choice

Given the following: 42.07% Na, 18.89% P, and 39.04% O, determine the empirical formula.

• NaPO₂
• Na₂PO₃
• Na₃PO₄
• NaPO₄

Poll

What is the best type of food?

• Italian

• Chinese

• Barbecue

• Mexican

• Other

Multiple Choice

What are the correct coefficients to balance the equation?

• 1, 1, 1, 1
• 1, 2, 1, 2
• 2, 1, 2, 1
• 2, 3, 2, 4

Multiple Choice

What is the percent by mass of oxygen in MgO?

• 20%
• 40%
• 50%
• 60%

Multiple Choice

A student calculated the number of moles of methane (CH₄) present in a 100g sample of a gaseous mixture. If the student determined that there’s 0.6 moles of methane present in the sample, what is the percent composition of methane in the sample?

• .096%

• 9.6%

• .9%

• 90%

Multiple Choice

What is the empirical formula of a compound that is 81.82% carbon and 18.18% hydrogen?

• C₃H₈

• CH₄

• C₂H₂

• C₄H₁₀

Multiple Choice

B₂H₆ + 3O₂ -->2 HBO₂ + 2 H₂O

What mass of O₂ will be needed to burn 36.1 g of B₂H₆?

• 13.8 g

• 3.86 g

• 124 g

• 198.3 g

Multiple Choice

What is the percent yield of the following reaction if 145g of P₂O₅ reacts with 40 grams of water, but you only collect 112 grams of phosphoric acid?

3 H₂O + P₂O₅ -> 2H₃PO₄

• 80%

• 85%

• 77%

• 58%

Multiple Choice

Caproic acid, which is responsible for the foul odor of dirty socks, is composed of C, H, and O atoms. Combustion of a 0.225-g sample of this compound produces 0.512 g CO₂ and 0.209 g H₂O. What is the empirical formula of caproic acid?

• CH₂O

• C₂H₂O

• C₃H₆O

• C₃H₄O₂

Multiple Choice

Fe + S --> FeS
If 7.62g Fe react with 8.67g S, what is the limiting reactant?

• Fe
• S
• FeS
• none 

Multiple Choice

What is the mass of 5.43x10²⁴ molecules of BeO?

• 171 g

• 3.29 x10⁴⁸ g

• 0.361 g

• 7.83 x 10²⁵ g

Multiple Choice

What is the limiting reactant if 10 moles of NH₃ react with 30.0 moles of NO?

4NH₃+ 6NO --> 5N₂ + 6H₂O

• NH₃

• NO

• N₂

• water

Multiple Choice

A 4.175 gram sample of a certain hydrate of copper (II) sulfate, CuSO4•xH2O, is heated until all the water is driven off. The resulting anhydrous compound weighs 3.120 grams. What is the formula of the hydrate?

• CuSO4•H2O

• CuSO4•3H2O

• CuSO4•6H2O

• CuSO4•4H2O

Multiple Choice

A 5.018 gram sample of a certain hydrate of magnesium sulfate, MgSO4•xH2O, is heated until all the water is driven off. The resulting anhydrous compound weighs 2.449 grams. What is the formula of the hydrate?

• MgSO4•9H2O

• MgSO4•8H2O

• MgSO4•7H2O

• MgSO4•6H2O