Chemmisstrrry

What is a chemical change?

Pick out the changes from the following:

• Tooth Decay

• a person sitting on a chair

• Revolution of earth

• Month to another month

• a non-working pendulum

What is a physical change?

Haber's process is an example of _____________

• Irreversible chemical change

• Reversible chemical change

Is this an example of a physical or chemical change?

• physical

• chemical

A __________ is a mixture that is formed when a solid is dissolved in a liquid.

• Chemical compound
• Solution
• Endothermic reaction
• Exothermic reaction

Melting a chocolate bar?

• Physical Change
• Chemical Change 

What type of change is an earthquake?

• Chemical

• unperiodic

• man-made

• reversible

Which one is not the characteristics of a physical change ?

• They are changes in the physical properties of substance.

• They are often irreversible

• Rearrangement of molecules take place

• No new substances are formed

Is this an example of a physical or chemical change?

• physical

• chemical