Chemical Reactions Test

When a new substance forms as a result of a chemical reaction, what type of change has occurred?

• Chemical Change

• Physical Change

Which is NOT an indication of a chemical change?

• Temperature Change

• Shape Change

• Formation of a precipitate

• Production of light

What is the left part of a chemical equation called?

2H_{2 +} O₂ --> 2H₂O

• Reactants

• Yields

• Products

• Chemical Equation

What is the right part of a chemical equation called...

2H_{2 +} O₂ --> 2H₂O

• Reactants

• Yields

• Products

• Chemical Equation

True or False

In a chemical reaction, no new atoms are created, and no atoms are destroyed.

• TRUE

• FALSE

Which statement is not a description of a chemical reaction?

• A solid is dropped into a beaker of liquid and a gas is released.

• A solid is dropped into a beaker of liquid and an explosion occurs.

• Two liquids are mixed in a beaker and a solid forms at the bottom of the beaker.

• A liquid is heated in the sun and half of it evaporates.

When a scientist mixed two chemicals, an exothermic reaction takes place. Which of the following would be proof that the reaction was exothermic?

• a change of color
• a change of state
• a temperature decrease
• a temperature increase

In the reaction, methane + oxygen turns into carbon dioxide + water, the methane and oxygen are called _______________.

• reactants
• products
• neutrals
• energizers

Increasing the concentration of a reactant in a chemical reaction will _____________.

• decrease the rate of the reaction
• stop the reaction from happening
• increase the rate of the reaction
• have no effect on the rate of the reacion

Which of the following is a chemical change?

• the rusting of iron
• dissolving salt in water
• melting an ice cube
• bending a copper wire