Chemistry Questions and Answers - Form 1 End Term 1 Exams 2022

QUESTIONS

Answer all the questions in the spaces provided.

1. State any two branches of Chemistry. (2 mks)
2.                    
   1. What is a drug? (1 mk)
   2. List any three frequently abused drugs? (3 mks)
3. Outline four roles of Chemistry in the society. (4 mks)
4. Identify the following apparatus as they are used and found in a Chemistry Laboratory.(4 mks)
   
5.                      
   1. Define a flame as used in Chemistry . (1 mk)
   2. State the differences between luminous and non-luminous flames. (4 mks)
      

      Luminous	Non-Luminous

6.                     
   1. Identify the following apparatus and state its function as used in the laboratory.(2 mks)
      
   2. State the uses of the labeled parts; A, B, C and D. (4 mks)
      A –
      B –
      C -
      D -
7.                        
   1. State the three states of matter. (1 ½ mks)
   2. Identify the following processes that show the changes of state that occur when a substance is heated and then cooled. (6 mks)
      
8.                        
   1. What is a mixture? (1 ½ mks)
   2. State any four physical methods of separating mixtures. (2 mks)
9.                        
   1. Define the following terms:- (3 mks)
      1. Atom –
      2. Compound –
      3. An element –
   2. State the differences between temporary and permanent changes. (4 mks)
      

      Temporary	Permanent

10. List any six laboratory rules and regulations of a Chemistry Laboratory. (6 mks)
11. Name any four career opportunities of Chemistry as a subject. (4 mks)
12. State why most of laboratory apparatus are made of glasses. (3 mks)
13. State three long-term effects of drug-abuse. (3 mks)
14. The following diagrams represent a non-luminous flame of a Bunsen burner.
    
    
    1. Name the parts of the flame labeled A, B and C. (1 ½ mks)
    2. Which part is the hottest? ( ½ mks)
    3. A non-luminous flame is preferred for heating. Explain. (2 mks)
    4.                    
       1. Name the other type of flame produced by a Bunsen burner. (1 mk)
       2. Under what conditions does the Bunsen burner produce the flame you have named in d(i) above? (1 mk)
15. State the effect of impurities on melting on boiling points. (1 mk)
16.                    
    1. Name the elements present in the following compounds:
       1. Calcium carbonate –
       2. Magnesium nitride -
    2. Write a word equation for the reaction between:-
       1. Carbon and Oxygen.
       2. Sodium and oxygen.

MARKING SCHEME

Answer all the questions in the spaces provided.

1. State any two branches of Chemistry. (2 mks)
   physical chemistry
   inorganic chemistry
2.                    
   1. What is a drug? (1 mk)
      A substance that alters the normal functioning of the body when taken
   2. List any three frequently abused drugs? (3 mks)
      tobacco
      cocaine
      bhang
3. Outline four roles of Chemistry in the society. (4 mks)
   manufacture of drugs
   as a career subject
   food production
   manufacture of detergents
4. Identify the following apparatus as they are used and found in a Chemistry Laboratory.(4 mks)
   
   
   1. conical flask
   2. flat bottomed flask
   3. filter funnel
   4. motar and pestle
5.                      
   1. Define a flame as used in Chemistry . (1 mk)
      is a zone of burning gases
   2. State the differences between luminous and non-luminous flames. (4 mks)
      

      Luminous	Non-Luminous
      has four zones	three zones
      large and steady	small and steady
      emits soot	non-sooty
      quiet	noisy
      not so hot	very hot

6.                     
   1. Identify the following apparatus and state its function as used in the laboratory.(2 mks)
      
      bunsen burner - used for heating substances during experiments
   2. State the uses of the labeled parts; A, B, C and D. (4 mks)
      collar - regulates the amount of air that gets into the chimney
      air hole - allows air to enter the chimney and mix with laboratory gas
      chimney - space where the laboratory gas mixes with air
      base - supports other parts of the bunsen burner
7.                        
   1. State the three states of matter. (1 ½ mks)
      solid
      liquid
      gases
   2. Identify the following processes that show the changes of state that occur when a substance is heated and then cooled. (6 mks)
      
      A - melting
      B - vaporisation
      C - freezing
      D - condensation
      E - sublimation
      F - deposition
8.                        
   1. What is a mixture? (1 ½ mks)
      consists of two or more substances combined together that one may use physical means to separate
   2. State any four physical methods of separating mixtures. (2 mks)
      distillation
      filtering
      use of magnets
      winnowing
9.                        
   1. Define the following terms:- (3 mks)
      1. Atom – the smallest particle of an element that can take part in a chemical change
      2. Compound –  a pure substance that is made up of two or more elements that are chemically combined
      3. An element – a pure substance that can not be split into simpler substances by chemical means
   2. State the differences between temporary and permanent changes. (4 mks)
      

      Temporary	Permanent
      reversible	irreversible
      no new substance formed	new substance is formed
      no change in mass	change in mass

10. List any six laboratory rules and regulations of a Chemistry Laboratory. (6 mks)
    never taste or eat
    never run around in the laboratory
    never smell the gases directly
    always extinguish flames that are not in use
    always use  a claen spatula for scooping substances
    always consult your teacher
11. Name any four career opportunities of Chemistry as a subject. (4 mks)
    chemistry teacher
    pharmacy
    engineer
    a doctor
12. State why most of laboratory apparatus are made of glasses. (3 mks)
    not react with most of the substances
    easy to clean
    transparent
13. State three long-term effects of drug-abuse. (3 mks)
    stress
    depression
    hallucination
14. The following diagrams represent a non-luminous flame of a Bunsen burner.
    
    
    1. Name the parts of the flame labeled A, B and C. (1 ½ mks)
       A - pale blue flame
       B - green blue zone
       C - almost colourless
    2. Which part is the hottest? ( ½ mks) A
    3. A non-luminous flame is preferred for heating. Explain. (2 mks)
       produces alot of heat compared to that of luminous flame
    4.                    
       1. Name the other type of flame produced by a Bunsen burner. (1 mk)
          luminous
       2. Under what conditions does the Bunsen burner produce the flame you have named in d(i) above? (1 mk)
          when the air hole is partially opened or closed
15. State the effect of impurities on melting on boiling points. (1 mk)
    lowers the melting point and rises the boiling point
16.                    
    1. Name the elements present in the following compounds:
       1. Calcium carbonate – calcium, carbon and oxygen
       2. Magnesium nitride - magnesium and nitrogen
    2. Write a word equation for the reaction between:-
       1. Carbon and Oxygen. 
          carbon + oxygen → carbon(IV) oxide
       2. Sodium and oxygen.
          Sodium + Oxygen → Sodium oxide