Chemistry Questions and Answers - Form 1 Mid Term 1 Exams 2021

CHEMISTRY
FORM 1
MID TERM
TERM 1

INSTRUCTIONS

• Answer all the questions

1. Putting off flames after use is one of the safety rules in the laboratory. State five other rules. (5mks)
2.      
   1. Name three frequently abused drugs.(3mks)
   2. State two long-term effects of drug abuse.(2mks)
3.         
   1. What is sublimation?(1mk)
   2. State four substances that sublimes.(2mks)
4. The diagram below shows various states of matter. Study it and answer the questions that follow.
   
   
   1. State the processes labeled A to F.(3mks)
5. Name two method of separating miscible liquids.(2mks) 
6. Study the flame shown below.
   
   
   1. Name the type of flame shown above.(1mk)
   2. Label the regions A, B and C.(3mks)
   3. Which region is the hottest?(1mk)
   4. State two reasons why the above flame is preferred for heating.(2mks)
   5. State the condition under which the above flame is produced.(1mk)
7. State 4 career areas studied in chemistry.(2mks)
8. State reasons why most laboratory apparatus are made of glass.(2mks)

MARKING SCHEME

1. Putting off flames after use is one of the safety rules in the laboratory. State five other rules. (5mks)
   • Always keep flammable substances away from flame.
   • Never smell gases directly, instead waft the gas towards your nose with your hand.
   • Label all the chemicals you are using to avoid confusion.
   • Never taste or eat anything in the laboratory to avoid poisoning.
   • Chemicals already used must always be disposed off safely to avoid contamination.
2.      
   1. Name three frequently abused drugs. (3mks)
      • Tobacco
      • Alcohol
      • Bhang
      • Khat (miraa)
        
        
   2. State two long-term effects of drug abuse. (2mks)
      • lung cancer
      • Heart failure
      • Liver problems
      • Mental disorder
3.     
   1. What is sublimation? (1mk)
      • It is a direct change from solid to gaseous without undergoing liquid state.
        
        
   2. State four substances that sublime. (2mks)
      • Aluminium chloride
      • Benzoic acid
      • Carbon (IV) oxide (dry ice)
      • Iodine
      • Anhydrous iron (III) chloride.
        
        
4. The diagram below shows various states of matter. Study it and answer the questions that follow.
   
   1. State the processes labeled A to E. (3mks
      A: melting
      B: Freezing
      C: Vaporization/ evaporation
      D: Condensation
      E: Sublimation.
      F: Deposition.
      
      
5. Name two method of separating miscible liquids. (2mks)
   • Simple distillation
   • Fractional distillation.
     
     
6. Study the flame shown below.
   
   1. Name the type of flame shown above. (1mk)
      • Non-luminous flame
        
        
   2. Label the regions A, B and C. (3mks)
      A – pale blue region
      B – Greenish blue region
      C – Almost colourless region.
      
      
   3. Which region is the hottest? (1mk)
      • A
        
        
   4. State two reasons why the above flame is preferred for heating. (2mks)
      • It’s very hot
      • Does not produce soot.
        
        
   5. State the condition under which the above flame is produced. (1mk)
      • When the air hole is open.
        
        
7. State 4 career areas studied in chemistry. (2mks)
   • Chemistry teacher
   • Laboratory technician
   • Pharmacist
   • Medical doctor
   • Public health officer.
     
     
8. State reasons why most laboratory apparatus are made of glass. (2mks)
   • Glass does not react with most laboratory reagents.
   • Easy to clean.
   • Easy visibility.