U1, L1: Chemical Reactions

What is a chemical reaction?

• The formation of new bonds in the product molecules

• The breaking up of bonds in the reactant molecules and forming new bonds in the product molecules

• The breaking up of bonds in the product molecules

• The formation of new bonds in the reactant molecules

Which of the following is an example of a thermal decomposition reaction?

• Burning of gasoline in a car engine

• Reaction of an acid with a salt

• Reaction between CO2 and water in photosynthesis

• Decomposition of copper carbonate by heat

What is the conclusion of the reaction between sodium nitrate and heat?

• Sodium nitrate decomposes into sodium nitrite and oxygen

• Sodium nitrate decomposes into sodium nitrite and hydrogen

• Sodium nitrate decomposes into sodium nitrite and water

• Sodium nitrate decomposes into sodium nitrite and carbon dioxide

What happens when a piece of magnesium ribbon is put in a beaker filled with blue copper sulphate solution?

• The blue color remains unchanged

• The blue color disappears and a yellow precipitate is formed

• The blue color disappears and a reddish brown precipitate is formed

• The blue color turns green

What is the reducing agent in the reaction between hydrogen and copper oxide?

• Water

• Copper oxide

• Copper

• Hydrogen

What is the oxidizing agent in the reaction between sodium and chlorine gas?

• Sodium

• Sodium ion

• Chlorine gas

• Sodium chloride

What is the conclusion of the reaction between copper sulphate and heat?

• Copper sulphate decomposes into copper oxide and Sulphur dioxide

• Copper sulphate decomposes into copper oxide and Sulphur trioxide

• Copper sulphate decomposes into copper oxide and water

• Copper sulphate decomposes into copper oxide and carbon dioxide

What is the conclusion of the reaction between copper hydroxide and heat?

• Copper hydroxide decomposes into copper oxide and Sulphur trioxide

• Copper hydroxide decomposes into copper oxide and oxygen

• Copper hydroxide decomposes into copper oxide and carbon dioxide

• Copper hydroxide decomposes into copper oxide and water vapor

What is the conclusion of the reaction between red mercuric oxide and heat?

• Red mercuric oxide decomposes into mercury and carbon dioxide

• Red mercuric oxide decomposes into mercury and water

• Red mercuric oxide decomposes into mercury and Sulphur trioxide

• Red mercuric oxide decomposes into mercury and oxygen

What is the conclusion of the reaction between zinc oxide and heat?

• Zinc oxide decomposes into zinc and oxygen

• Zinc oxide decomposes into zinc and water

• Zinc oxide decomposes into zinc and Sulphur trioxide

• Zinc oxide decomposes into zinc and carbon dioxide