Percentage of silver in the alloy, German Silver is:-

1. 2.5%

2. 1.5%

3. 10%

4. 0%

Mond's process is used for

1. Ni

2. Al

3. Fe

4. Cu

Aluminium is used as a reducing agent in the reduction of :-

1. Cr₂O₃

2. SnO₂

3. ZnO

4. HgO

Which of the following has a negative slope?

1. C $\to \hspace{0.17em}$CO

2. Fe $\to \hspace{0.17em}$Fe₂O₃

3. Mg $\to \hspace{0.17em}$MgO

4. All of the above

Out of the following which metal can be purified by the Van Arkel method?

1. Ti

2. Zr

3. Hf

4. All of these

Vapour phase refining can be carried out in case of 

1. Ni

2. Zr

3. Ti

4. All of these

Which of the following is leached with NaCN?

1. Ore of Al

2. Ore of Cu

3. Ore of Ag

4. Ore of Zn

Galena contains ZnS with PbS. Which of the following is used as depressant to stop ZnS to come with foam?

1. NaCN

2. Aniline

3. Pine Oil

4. H₂O

In the metallurgy of copper, the slag is -

1. FeSiO₃

2. CaCO₃

3. CaSiO₃

4. CaO

Serpek's method involves the heating of bauxite with 

1. NaOH

2. Na₂CO₃

3. N₂ + C

4. CaCO₃