1. What is an ion?

2. State two methods of softening hard water.

1. Differentiate between pest and parasites as used in agriculture.

2. Give an example each of a:

   α) pest;

   β) parasite.

1. What is work?

2. A force of 10N causes a body to move a distance of 5.2m in the direction of the force. Calculate the work done.

Name two diseases associated with the circulatory system of humans.

1. What is malnutrition?

2. State one symptom each of the following deficiency diseases:

   α) scurvy;

   β) rickets.

Draw the potassium atom and show the distribution of electrons in its shells.

[K = 19]

1. Define potential energy.

2. An object of mass 10kg is moving at a velocity of 2 m/s.

   Calculate the kinetic energy of the object.

State one example each of:

1. macro nutrients;

2. micro nutrients.

1. Explain the term hazard.

2. List two safety precautions against hazards in the teaching and learning of science.

In a tabular form state three differences between osmosis and diffusion.

1. What is weather?

2. State two differences between weather and season.

1. What is a fertile soil?

2. State two factors that cause loss of soil fertility.

1. What is a magnetic field?

2. Name two methods of making magnets.

Explain briefly the term teenage pregnancy.

Write the formula for each of the following compounds:

1. calcium chloride;

2. copper (I) oxide;

3. nitrogen (IV) oxide;

4. ammonia.

1. List three physical properties of soil.

2. What is the texture of clayey soil?

1. What are derived quantities?

2. State the S.I units of the following quantities:

   α) area;

   β) volume.

1. State two factors necessary for photosynthesis.

2. Explain the functions of each of the factors stated in (i).

1. Explain each of the following terms:

   1. Soft water;

   2. Hard water.

State three reasons why some seeds are nursed.