Page 2 - 2. HA-WS -13 Ch-5 CLASSIFICATION BY DOB.& NEWL.
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Q4. In electrolytic refining, the cathode is made up of
a) Pure metal b) Impure meta c) Alloy d) Metallic sal
[ A+Av ] (1mark)
.
Q5. Which of the following represent the correct order of decreasing reactivity?
a) Mg > Al > Zn > Fe
b) Mg > Zn > Al > Fe
c) Al > Zn > Fe > Mg
d) Mg > Fe > Zn > Al
[ U+Av ] (1mark)
Subjective-
Q.6.(a) Will you be able to check if water is hard by using a detergent?
(b) Why are the clothes rubbed with a brush or beaten with a clothes bar or agitated in
a washing machine while cleaning them with soap or detergent? [ A+Av ] (3mark)
Q.7. Why does micelle formation take place when soap is added to water? Will a micelle
be formed in other solvents such as ethanol also? [ A+Av ] (3mark)
Q.8. Explain the formation of scum when hard water is treated with soap with
necessary chemical equations. [ A+Av ] (3mark)
Q.9. What were the limitations(any three)of Newland’s Law of Octaves?
[A+Av ] (3mark)
Q10. (a)What change will you observe by testing soap with litmus paper (blue or red)?
[ A+Av ] (5mark)
(b) Explain the mechanism of cleansing action of soap. -------------------------------------------
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