BECEzone

THE WEST AFRICAN EXAMINATIONS COUNCIL
GHANA

Basic Education Certificate Examination

SCIENCE 2021

THEORY QUESTIONS

PART II
[60 marks]


Answer all of Question 1

      1. State what happens when photosynthesis occurs in a leaf.

      2. What is pollination?

    1. Explain briefly why the mass of lumpy charcoal remains unchanged when ground into powder but the mass of the same lump changes when heated to burn.

      1. What is a physical quantity?

      2. State two physical quantities.

    2. State two importance each of:

      1. light

      2. temperature

      In crop production

      1. What is hardness of water?

      2. Give one example each of a natural source of water that is:

        α) hard water;

        α) soft water;

      1. What is the end-product of the digestion of meat?

      2. What is the end-product of the digestion of cassava?

      3. What is the end-product of the digestion of palm-oil?

      1. Give one effect of soil type in vegetable crop production.

      2. Give one effect of nearness to market in vegetable crop production.

      3. Give one effect of nearness to source of water in vegetable crop production.

      1. Explain briefly why an eclipse occurs.

      2. Name the two types of eclipse.

      1. Explain the term convection as applied to heat transfer.

      2. Give two reasons why convection does not occur in solids.

      1. Give two effects of each of the following soil physical properties on maize cultivation

      2. texture

      3. water holding capacity

    1. Use any three of the following organisms to construct a food chain: Hawk, grasshopper, man, grass, toad, grasscutter.

      1. Consider the following elements and state which element(s) is/are metals: 11Na, 7N, 6C, 3Li.

      2. Explain briefly what is observed when pieces of each of the following metals are dropped into two separate test tubes each containing dilute hydrochloric acid:

        α) magnesium;

        β) silver.

      1. State two important components of the soil that help:

        α) Crops to grow well;

        β) To maintain good soil structure.

      1. Explain how energy in a windmill is obtained.

      2. State one source of renewable energy.

      1. Explain why steel is preferred to iron in building construction.

      2. State two ways of preventing rusting.

    1. State three ways of preventing indigestion.

    1. State three ways by which the atmosphere in an industrial area is polluted.

      1. Write the word equation for each of the following reactions between:

        α) calcium and oxygen

        β) nitrogen and hydrogen

      2. State the hazard that could be prevented when each of the following protective materials are used in the laboratory:

        α) gas mask

        β) goggles

      1. If a cuboid of weight 100 N has sides 5 cm by 10 cm, calculate the:

        α) Area of the cuboid;

        β) Pressure exerted by the cuboid when it lies on its side.

      1. Explain the term mixed farming.

      2. State two advantages of mixed farming.