Which of the following pairs does not contain a coinage metal ?

(A) Copper and gold

(B) Silver and gold

(C) Zinc and gold

(D) Copper and silver

The filament of an electric bulb is made of--

(A) Iron

(B) Nichrome 

(C) Tungsten

(D) Graphite

The two elements that are frequently used for making transistors are--

(A) Boron and aluminium

(B) Silicon and germanium

(C) Iridium and tungsten

(D) Niobium and columbium

Which of the following gases is not known as a greenhouse gas?

(A) Carbon dioxide

(B) Methane

(C) Nitrous oxide

(D) Chlorofluorocarbons

Match the following.

Consider the following statements regarding graphite:
$1.$ It is an allotrope of carbon.
$2.$ It is a good conductor of heat and electricity.
$3.$ It can be artificially produced.

Select the correct statement from the following.

Chemical formula for water glass is--

(A) Na₂SiO₃

(B) Al₂O₃

(C) NaAlO₂

(D) CaSiO₃

The gases used in different types of welding would include-

(A) Oxygen and hydrogen

(B) Oxygen, acetylene, and argon

(C) Oxygen, acetylene

(D) Oxygen, hydrogen, acetylene and, nitrogen