Question

1. a rock that contains a metal or other economically useful mineral is called a(n) (4

gem
gemstone
ore
crystal

1. to extract the precious metal from an ore, you often have to use (4 points)

oil
chemical and salt
salt
heat and salt

Explanation:

• For question 4, an ore is defined as a rock that contains a metal or other economically useful mineral. Gems and gemstones are typically precious or semi - precious stones valued for beauty and rarity, and a crystal is a solid material with a regular internal atomic structure.
• For question 5, to extract precious metals from an ore, chemical processes are often involved, and sometimes salts can be part of the extraction methods. Oil is not typically used for metal extraction from ore in the main processes, and just salt or heat and salt alone are not comprehensive methods for metal extraction.

Answer:

1. C. ore
2. B. chemical and salt