1. Which metal always found in free state?
2. Silver metal is obtained by—
A. Magnetic separation
B. Parke’s process
C. Forth floatation process
D. Carbon reduction process
3. The most abundant element in the earth crust is—
4. Which of the following metals do not form amalgam?
5. The compound of a metal is found in nature is called—
6. Which metal is used for the extraction of metals from their oxides by reduction?
7. A naturally occurring substance from which a metal can be profitably extracted is called—
8. Which of the following metal is obtained by leaching its over with dilute cyanide solution?
9. Which of the following metals is extracted by thermal reduction process?
10. Most of the explosions in mines occur due to the mixing of—
A. Oxygen with acetylene
B. Carbondioxide with ethane
C. Hydrogen with oxygen
D. Methane with air