Chemistry Interim Review AG

Chemistry Interim Review AG

You will do great!

Multiple Choice

Magnesium is a highly flammable element which is easily combustible in the presence of oxygen:

2Mg + O₂ --> ?? + heat

What is the UNKNOWN PRODUCT?

• MgO

• MgO2

• 2MgO

• Mg₂O₂

Multiple Choice

Magnesium is a highly flammable element which is easily combustible in the presence of oxygen:

2Mg + O₂ --> ?? + heat

How many atoms would you find on the product side of the equation?

• 1

• 2

• 3

• 4

Multiple Choice

Sodium Oxide (Na₂O) can react with hydrochloric acid (HCl) to produce sodium chloride (NaCl) and water (H2O) according to the following equation:

Na₂O + 2HCl -> 2NaCl + H₂O

How many total atoms are present before and after the reaction?

• 2 before and 2 after

• 3 before and 3 after

• 5 before and 5 after

• 7 before and 7 after

Multiple Choice

Consider the incomplete chemical equation,

CO₂(g) + H₂O(l) → ?

Assuming the reactants are balanced and we start with 5 carbon dioxide molecules and 10 water molecules, how many oxygen atoms would you expect to find in the products?

• 10 oxygen atoms

• 15 oxygen atoms

• 20 oxygen atoms

• 25 oxygen atoms

Incomplete reaction:

CO₂(g) + H₂O(l) → ?

How many carbon atoms in the reactant side?

How many oxygen atoms in the reactant side?

Open Ended

CO₂(g) + H₂O(l) → ?

1. How many carbon atoms in the reactant side?

2. How many oxygen atoms in the reactant side?

3. If I tripled the amount of carbon dioxide and water, how many carbon will there be?

Multiple Choice

In 1909 Fritz Haber discovered the workable conditions under which nitrogen, N₂(g), and hydrogen, H₂(g), would combine to produce ammonia. The conditions included medium temperature (~500^oC), very high pressure (~351kPa), and an iron catalyst. The reaction is represented by the equation:

N₂(g) + 3H₂(g) → 2NH₃(g)

How many moles of nitrogen are needed to produce 1.20 moles of ammonia gas?

• 0.60 mol N₂

• 1.21 mol N₂

• 1.67 mol N₂

• 2.40 mol N₂

1 mole (of anything we study in Chemistry) = 6.022 x 10²³ (of anything)

Remember that this never changes and this relationship has been an accepted value for the last 100 years.

Multiple Choice

Determine the number of molecules contained in 1 mole of sodium sulfate.

• 1.204 x 10²⁴ ions

• 1.807 x 10²⁴ ions

• 2.007 x 10²³ ions

• 6.022 x 10²³ ions

Multiple Choice

Students in Ms. Brown demonstrated several chemical reactions but the data did not represent the law of conservation of matter in any of the four experiments. Kai and Maria are about to add 3 grams of magnesium (Mg) to a test tube of 30 grams of hydrochloric acid (HCl). They covered their container with a balloon as a seal. If the girls expect a chemical change as well as evidence of the law of conservation of matter, choose ALL of the predictions that are appropriate? Use the IMAGE to help you answer this question.

• There will be a rapid evolution of gas.

• The mass of the products will equal 33g.Eliminate

• The solid magnesium metal will disappear.

• The balloon covering the container will expand.

• There will be a dramatic change in temperature.