17
MCQ (Multiple Correct Answer)
Which of the following statements is correct about the role of substances added in the froth floatation process?
A
Collectors enhance the non-wettability of the mineral particles.
B
Collectors enhance the wettability of gangue particles.
C
By using depressants in the process two sulphide ores can be separated.
D
Froth stabilisers decrease wettability of gangue.
18
MCQ (Multiple Correct Answer)
In the froth floatation process, zinc sulphide and lead sulphide can be separated by ............ .
A
using collectors
B
adjusting the proportion of oil to water
C
using depressant
D
using froth stabilisers
19
MCQ (Multiple Correct Answer)
Common impurities present in bauxite are ............. .
A
CuO
B
ZnO
C
$\mathrm{Fe}_2 \mathrm{O}_3$
D
$\mathrm{SiO}_2$
20
MCQ (Multiple Correct Answer)
Which of the following ores are concentrated by froth floatation?
A
Haematite
B
Galena
C
Copper pyrites
D
Magnetite
21
MCQ (Multiple Correct Answer)
Which of the following reactions occur during calcination?
A
$\mathrm{CaCO}_3 \longrightarrow \mathrm{CaO}+\mathrm{CO}_2$
B
$2 \mathrm{FeS}_2+\frac{11}{2} \mathrm{O}_2 \longrightarrow \mathrm{Fe}_2 \mathrm{O}_3+4 \mathrm{SO}_2$
C
$\mathrm{Al}_2 \mathrm{O}_3 \cdot x \mathrm{H}_2 \mathrm{O} \longrightarrow \mathrm{Al}_2 \mathrm{O}_3+x \mathrm{H}_2 \mathrm{O}$
D
$\mathrm{ZnS}+\frac{3}{2} \mathrm{O}_2 \longrightarrow \mathrm{ZnO}+\mathrm{SO}_2$