Give reasons.
1. Wall paints are always in liquid form
Answers
Paint has three components: pigment, binder and solvent. Pigment is colour chemical substance in paint. Pigments are solids, so we could not use them to paint by themselves. It is difficult to apply pigments to the surface directly.
They will not spread evenly and will not stick to the surface. Hence binder is mixed with pigment in order to glue the pigment particles to glue together and also to make them stick to surface. After mixing binder to the pigment, we get thick substance which is difficult to spread. Hence a solvent in liquid form is used to dissolve the pigment and binder.
Once the pigment and binder is dissolved in solvent, the mixture which is in liquid form and less viscous will spread evenly. Once the paint is spread out, solvent evaporates leaving the paint evenly applied and in dried form.