Chemistry 2.4

Multiple Choice

• a

  The mass will decrease because matter is lost in this reaction.

• b

  The mass will stay the same because the gases produced in the reaction are kept inside the container.

• The mass will increase because the solids react with gas to produce more solids.

• There is not enough information to predict whether the mass will increase, decrease, or stay the same during the reaction in a closed container.

Multiple Choice

A reaction produces a gas, which is collected in a glass cylinder. When a glowing splint is placed inside the container, it burns brightly, as shown. Which gas was produced in the reaction?

• hydrogen

• oxygen

• cardon dioxide

• ammonia

Multiple Choice

A white powder is added to a solution. The images show observations made before the powder is added, just after the powder has been added, and a little while later. (The liquid in the small beaker is phenol red solution.) What evidence shows that a chemical change has taken place?

• gas is produced

• pH changes

• temperature changes

• all of these

Multiple Select

Choose all that are examples of chemical changes.

• burn

• rot

• rust

• decompose

• derment

Multiple Select

Choose all that are examples of chemical changes.

• explode

• corrode

• react

• cut

• boil

Multiple Choice

During a chemical change, the composition of matter always changes.

• True

• False

Multiple Choice

Which is not an indicator of a chemical change occuring

• transfer of energ

• change in color

• production of a gas

• formation of a precipitate

• change in size