Applications of physical and chemical changes Practice exercise 3

A student heated salty water. Steam rose, and white salt crystals remained in the container as shown below.What type of change occurred during the separation of salt from the water?  (1 mark)

A student heated salty water. Steam rose, and white salt crystals remained in the container as shown below.What type of change occurred during the separation of salt from the water?  (1 mark)

A student heated salty water. Steam rose, and white salt crystals remained in the container as shown below.What type of change occurred during the separation of salt from the water?  (1 mark)

At a hotel, mandazi is reheated using steam instead of frying. Why is steaming preferred for reheating?   (1 mark)

At a hotel, mandazi is reheated using steam instead of frying. Why is steaming preferred for reheating?   (1 mark)

At a hotel, mandazi is reheated using steam instead of frying. Why is steaming preferred for reheating?   (1 mark)

During a hot afternoon, Wanjiku adds ice cubes to her mango juice as shown below. Why does the juice become cold?  (1mark)

During a hot afternoon, Wanjiku adds ice cubes to her mango juice as shown below. Why does the juice become cold?  (1mark)

During a hot afternoon, Wanjiku adds ice cubes to her mango juice as shown below. Why does the juice become cold?  (1mark)

During a hot afternoon, Wanjiku adds ice cubes to her mango juice as shown below. Why does the juice become cold?  (1mark)

While boiling water for tea, Ali notices water droplets forming on the kitchen window. Why does this happen?    (1mark)

While boiling water for tea, Ali notices water droplets forming on the kitchen window. Why does this happen?    (1mark)

While boiling water for tea, Ali notices water droplets forming on the kitchen window. Why does this happen?    (1mark)

Brian stores his leftover githeri in a refrigerator. Why does the food stay fresh for a longer time?   (1mark)

Brian stores his leftover githeri in a refrigerator. Why does the food stay fresh for a longer time?   (1mark)

Mary uses a steam iron to press her school uniform. Why does the steam help remove wrinkles?    (1mark)

Mary uses a steam iron to press her school uniform. Why does the steam help remove wrinkles?    (1mark)

Mary uses a steam iron to press her school uniform. Why does the steam help remove wrinkles?    (1mark)

A family uses charcoal in a jiko to cook ugali. What type of change happens when charcoal burns? (1 mark)

A family uses charcoal in a jiko to cook ugali. What type of change happens when charcoal burns? (1 mark)

A family uses charcoal in a jiko to cook ugali. What type of change happens when charcoal burns? (1 mark)

Otieno boiled water fetched from a river before drinking it. What type of change occurs when river water is boiled?  (1 mark)

Otieno boiled water fetched from a river before drinking it. What type of change occurs when river water is boiled?  (1 mark)

Otieno boiled water fetched from a river before drinking it. What type of change occurs when river water is boiled?  (1 mark)

The diagram below shows a hoe left outside in the rain. Rust has formed on its blade. What type of change has taken place on the hoe?   (1 mark)

The diagram below shows a hoe left outside in the rain. Rust has formed on its blade. What type of change has taken place on the hoe?   (1 mark)

The diagram below shows a hoe left outside in the rain. Rust has formed on its blade. What type of change has taken place on the hoe?   (1 mark)

Nthenya candle broke into small pieces. She melted the wax and poured it into a mold to make a new candle. What type of change took place when Nthenya melted and reshaped the candle?  (1 mark)

Nthenya candle broke into small pieces. She melted the wax and poured it into a mold to make a new candle. What type of change took place when Nthenya melted and reshaped the candle?  (1 mark)

Nthenya candle broke into small pieces. She melted the wax and poured it into a mold to make a new candle. What type of change took place when Nthenya melted and reshaped the candle?  (1 mark)