The graph of PV vs P for a gas is:

1. Parabolic
2. Hyperbolic
3. A straight line parallel to X axis
4. A straight line passing through origin

Which metal gives hydrogen upon reaction with all of the following - Acid, alkali, water?

1. Iron
2. Zinc
3. Magnesium
4. Lead

Isotopes differ in number of :

1. Electrons
2. Protons
3. Neutrons
4. Positive charge

The substance which leaves a black residue on heating is :

1. Zinc carbonate
2. Copper nitrate
3. Lead carbonate
4. Ammonium dichromate.