Chemistry of Oxygen

Copper is oxidized by oxygen into copper (II) oxide. When you completely oxidize 6.4 gram copper, how many gram of oxide will you get?

• 6 g

• 7 g

• 8 g

• 9 g

How many grams of potassium permanganate are needed to produce 33.6 litters of oxygen gas?

• 473 g

• 474 g

• 475 g

• 476 g

Dissolve 6.5 grams zinc in excess amount of hydrochloric acid. The amount of hydrogen gas produced will be enough to reduce m grams of copper (II) oxide. The value of m is...

• 8

• 9

• 10

• 11

How many grams is remained after completely burning 100 grams of lime stone?

• 55 g

• 56 g

• 57 g

• 58 g

How many percent of oxygen are in the air?

• 19%

• 20%

• 21%

• 22%

How many percent of nitrogen are in the air?

• 79%

• 50%

• 21%

• 95%

How oxygen is separated from the air?

• Liquefaction of the air.

• Cool it to -200oC, then slowly heat up to -183oC.

• Freeze it to extreme low temperature, then separate the nitrogen, argon, and oxygen at different temperature

• Electrolysis.

Oxygen can be produced in the laboratory from...

• KMnO₄

• KClO₃

• H₂O₂

• NaNO₃

Sulfur dioxide can continue to be oxidized by oxygen. The reaction is...

• 2SO₂ + O₂ --> 2SO₃

• 2SO₃ + O₂ --> 2SO₂

• 4SO₂ + 5O₂ --> 2S₂O₅

• 2SO₂ + O₂ --> 2S₂O₃

Carbon monoxide is toxic because...

• It will react with oxygen to make CO₂

• It will take up oxygen from the air, so human don't have enough oxygen to breath if staying in close environment.

• It will react with water to produce oxygen.

• It will react with carbon dioxide to produce carbon.