Understanding Changes in Matter

What is an example of a reversible change?

• Burning wood to ash

• Melting ice into water

• Rusting iron

• Dissolving sugar in water

What happens to ice when heat is added?

• Ice becomes denser and sinks when heat is added.

• Ice evaporates into vapor when heat is added.

• Ice melts into water when heat is added.

• Ice turns into a solid block when heat is added.

What is the process called when water turns into ice?

• Evaporation

• Freezing

• Melting

• Condensation

Is cooking a raw egg a reversible or irreversible change?

• Temporary change

• Reversible change

• Chemical change

• Irreversible change

What happens to paper when it is burned?

• Paper turns into ash, carbon dioxide, and water vapor when burned.

• Paper transforms into plastic when burned.

• Paper produces smoke and turns into metal.

• Paper melts into a liquid form.

Can you turn a cut piece of paper back into a whole sheet?

• You can glue the pieces together to make it whole.

• No, you cannot.

• Folding the paper can restore its original form.

• Yes, you can use tape to reattach it.

What is the term for changing matter by pushing, pulling, or twisting?

• Mechanical deformation

• Chemical reaction

• Thermal expansion

• Phase transition

What is an example of an irreversible change?

• Melting ice

• Rusting iron

• Burning wood

• Dissolving sugar in water

What happens to matter when it is cooled after melting?

• Matter remains in a liquid state when cooled after melting.

• Matter turns into gas when cooled after melting.

• Matter solidifies when cooled after melting.

• Matter evaporates when cooled after melting.

Why is melting considered a reversible change?

• Melting is irreversible because it creates a new substance.

• Melting is reversible because the solid can return to its original state by cooling.

• Melting can only occur under high pressure, making it permanent.

• Once a solid melts, it cannot be solidified again.