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-p-Block elements - I — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistry-p-Block elements - I1 Mark
MCQ
In the electrolytic extraction of aluminium, cryolite is used
  • A
    To obtain more aluminium
  • ✓
    To decrease temperature to dissolve bauxite
  • C
    To protect the anode
  • D
    As reducing agent
✓

Answer

Correct option: B.
To decrease temperature to dissolve bauxite
b
(b) Cryolite $N{a_3}Al{F_6}$ is added

(1) To decrease the melting temp from $2323\,K$ to $1140\,K$

(2) To increase the electrical conductivity of solution

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