Unit 8 AP Chemistry

Hello World

• 2 : 3

• 1 : 2

• 1 : 1

• 1 : 3

Tags

NGSS.HS-PS1-7

In stoichiometry, chemists are mainly concerned with

• mole and mass relationships in chemical reactions.

• the types of bonds found in compounds.

• energy relationships in chemical reactions.

• the speed with which chemical reactions occur.

Tags

NGSS.HS-PS1-7

If a chemical reaction involving substance A and B stops when substance B is completely used up, then substance B is referred to as the

• excess reactant.

• limiting reactant.

• primary reactant.

• primary product.

In most chemical reactions the amount of product obtained is

• more than the theoretical yield.

• equal to the theoretical yield.

• more than the percent yield.

• less than the theoretical yield.

Tags

NGSS.HS-PS1-7

After a reaction is complete you still have some of one of the reactants left unreacted. That reactant is know as

• primary reactant.

• excess reactant.

• limiting reactant.

• primary product.

Tags

NGSS.HS-PS1-7

If % yield is 100% then which of the following is true?

• actual yield is greater than theocratical yield

• actual yield is less than theocratical yield

• actual yield is equal to theocratical yield

• there is no limiting reactant

Tags

NGSS.HS-PS1-7

Which of the following would be investigated in reaction stoichiometry?

• the types of bonds that break and form when acids reacts with metals

• the mass of potassium required to produce a known mass of potassium chloride

• the amount of energy released in chemical reactions

• the mass of hydrogen and oxygen in water

Tags

NGSS.HS-PS1-7

Musical instruments like trumpets and trombones are made from an alloy called brass. Brass is composed of copper and zinc atoms and appears homogeneous under an optical microscope. The approximate composition of most brass objects is a 2:1 ratio of copper to zinc atoms, but the exact ratio varies from one piece of brass to another. a) Would you classify brass as an element, a compound, a homogeneous mixture, or a heterogeneous mixture? b) would it be correct to say that brass is a solution?

Tags

NGSS.MS-PS1-1

Classify the following as a pure substance or a mixture. If a mixture, indicate whether it is homogeneous or heterogeneous. a) rice pudding, b) sea water, c) magnesium, d) crushed ice

Which separation method is better suited for separating a solution of sugar and water into pure substances, filtration or distillation? Explain your choice