EASY
Lower Secondary Stage 8
IMPORTANT
Earn 100

Copper is a shiny metal. A piece of it is heated in oxygen. Its surface becomes dull and black. Name the compound that is made in this chemical change.

Important Questions on Elements, Compounds and Mixtures

MEDIUM
Lower Secondary Stage 8
IMPORTANT
Cambridge Lower Secondary Science Stage 8 : Student's book>Chapter 4 - Elements, Compounds and Mixtures>End of chapter review>Q 8
Copper is a shiny metal. A piece of it is heated in oxygen. Its surface becomes dull and black. Describe how the compound is different from copper.
EASY
Lower Secondary Stage 8
IMPORTANT
Cambridge Lower Secondary Science Stage 8 : Student's book>Chapter 4 - Elements, Compounds and Mixtures>End of chapter review>Q 9
A chemical reaction between hydrochloric acid and magnesium produces magnesium chloride MgCI2. Is magnesium chloride an element, compound or mixture?
MEDIUM
Lower Secondary Stage 8
IMPORTANT
Cambridge Lower Secondary Science Stage 8 : Student's book>Chapter 4 - Elements, Compounds and Mixtures>End of chapter review>Q 10

Some air is pumped into a bicycle tyre.

  • Predict what will happen to the amount of gas pressure inside the tyre as air is pumped in.
  • Use particle theory to explain your prediction.
MEDIUM
Lower Secondary Stage 8
IMPORTANT
Cambridge Lower Secondary Science Stage 8 : Student's book>Chapter 4 - Elements, Compounds and Mixtures>End of chapter review>Q 11
Use particle theory to explain why you can compress a gas but not a liquid.
MEDIUM
Lower Secondary Stage 8
IMPORTANT
Cambridge Lower Secondary Science Stage 8 : Student's book>Chapter 4 - Elements, Compounds and Mixtures>End of chapter review>Q 12
Rock salt is found in the ground. It is a mixture of rock particles and salt. Describe how you would produce pure, dry salt from rock salt. You should explain the function of each step.
EASY
Lower Secondary Stage 8
IMPORTANT
Cambridge Lower Secondary Science Stage 8 : Student's book>Chapter 4 - Elements, Compounds and Mixtures>End of chapter review>Q 13

Rashin added a few drops of blue ink to a glass of cold water. Describe what she will see in the glass. Explain why.

EASY
Lower Secondary Stage 8
IMPORTANT
Cambridge Lower Secondary Science Stage 8 : Student's book>Chapter 4 - Elements, Compounds and Mixtures>End of chapter review>Q 13
Rashin added a few drops of blue ink to a glass of cold water. She then added a few drops of the ink to a glass of hot water. Describe how her observations would be different to what happened in the glass of cold water. Give a reason for this.
MEDIUM
Lower Secondary Stage 8
IMPORTANT
Cambridge Lower Secondary Science Stage 8 : Student's book>Chapter 4 - Elements, Compounds and Mixtures>End of chapter review>Q 14
Draw a diagram to show the particles in a piece of solid copper.