Year 4 Lo 6 – What are things made of?

Maria was experimenting with different liquids. She tried to mix two different liquids together in a drinking glass. This picture shows what happened to her mixture after being left to sit for 20 minutes. Which of the following materials were used in the mixture?

• Soap and milk

• Water and milk

• Oil and water

• Soap and oil

Why is washing liquid used for the washing of clothes in washing machine?

• It dissolves dirt in clothes, so clothes get clean.

• It makes clothes smell nicer.

• It helps the washing machine parts work better.

• It dissolves the clothes, so the dirt remains.

Which of the following solids is insoluble in water?

• Sugar

• Salt

• Sand

• Coffee

Are rusting and burning reversible or irreversible changes?

• Reversible Changes

• Irreversible Changes

1. Linda baked a cake. She was quite puzzled to see that during the cooking process her cake did not rise as usual. Something went wrong.

Usually a chemical reaction happens within the cake ingredients which allow the mixture to rise. Which one of the following ingredients do you think affects the rising process?

• Flour

• Milk

• Sugar

• Bicarbonate of Soda

Look at the above pictures.

Which of the following statements is correct?

• A and B are reversible changes.

• D is an irreversible change.

• C and D are reversible changes.

• B is a reversible change.

Which of the following is an example of an irreversible change?

• Inflating and deflating a balloon.

• Washing dirty clothes.

• Gluing back a broken vase.

• Melting wax.

Above are two groups of common materials which used around us.

What is the main difference between the materials in box A and box B?

• Materials in box A are heavier than box B.

• Materials in box A are natural, the materials in box B are manmade.

• Materials in box B are stronger than the materials in box A.

• Materials in box A are more expensive than the materials in box B.

Janice noted that wooden crates start to rot and disintegrate when left in a damp or humid place. This does not happen to plastic ones. Why does this happen?

• Wood and plastic are not different at all.

• Plastic is stronger than wood.

• Wood is a natural material which normally decomposes, plastic is not natural.

• Wood is not the ideal material to make crates.

Whilst visiting the national history museum Tina and Paul noted that most of the items used hundreds of years ago were made either of wood, metal, stone, cotton and clay. Why were these materials used and not others?

• People at that time loved these materials.

• Hundreds of years ago, modern manmade materials were not yet discovered, only natural materials were available.

• People at that time thought that these materials are very durable.

• These materials were very cheap at that time and looked more attractive.