Question

(a) Name the three classes in which elements are classified. Which was the first metal used by man?

(b) Name the metal and non-metal present in abundance in the earth crust.

Answer 1

(a)
Three classes in which elements are classified are:
Metals, Non-metals and Metalloids
Copper was the first metal used by man.

(b)
The metal which is present in abundance in earths crust is aluminium.
The non-metal which is present in abundance in the earth crust is oxygen.