Purity

which of the following is not a pure substance?

• sea water

• salt

• water

• 24-carat gold

What is the percentage purity of Gold in 18-carat Gold?

• 25%

• 50%

• 75%

• 100%

Answer explanation

The silver ring has the mark 925 on it. What is the percentage of purity of Silver in the ring?

• 90%

• 92.5%

• 95%

• 925%

Diamonds are made of the element ....

• Gold

• Silver

• Carbon

• Boron

Blue Diamond is a diamond which has some ..... element on it.

• Boron

• Nitrogen

• Nickel

• Silver

Which compound mainly present in the salt coming from sea water?

• sodium chloride

• magnesium chloride

• sodium sulfate

• calcium chloride