Chemistry Questions

Ionic compounds ______.

I. have high boiling point

II. have high melting point

III. conduct electricity in solution

Apart from proposing atomic theory, what did John Dalton researched on?

A ‘breath test’ used by traffic police to check drunken driving uses ____?

In a combination reaction there can be ______.

I. two or more than two reactants

II. two or more than two products

III. only one product

Which of the following statements are CORRECT?

I. Oxides of metals are generally basic.

II. Oxides of non-metals are generally acidic.

III. Non-metals are generally electro positive.

By volume, 21% of air is _______________.

An atom can achieve octet by ______.

I. sharing electron

II. gaining electron

III. losing electron

Brass gets discoloured in air because of the presence of which of the following gases in air  ?