1.

1. An experiment on the diffusion of ammonia and hydrogen chloride gases is carried out in a glass tube. The gases are given off by solutions held at each end of the tube.

   1. When the two gases meet, they react to produce a white solid, ammonium chloride.

      
      

   2. Which line (A–D) shows where the white solid is formed?

2.

1. In a gas, the particles are moving rapidly and randomly.Describe the movement of the particles in a liquid.

2. How does the movement of the particles in a solid change when it is heated?

3. What name is given to the process which happens when liquid water changes to water vapour at room temperature?

4. What is meant by the term freezing ?

3.

1. What is happening to the substance between C and D?

2. What is happening to the particles of the substance between A and B ?

   
   

Answers

1.

• The two gases meet in the center point of the glass tube

• Around the line bc the white solid will form

2.

• In liquid the particles are bound together but they are not bound that hard

• The particles in the liquid do change when they are heated as they start to move very quickly and also they vibrate

• Evaporation

• Freezing is when water is stored into a very low temperature where liquid transforms into solid

3.

• It melts more and the solid become more harder.

• The subtance wont turns into a solid but will become a chilled liquid