When NaOH is kept in air for a long time, it becomes wet and then it becomes dry due to formation of a solid crust ouer its surface. Explain the observations.

What happns when washing soda is kept in air for long time?

When a moist bread is kept exposed in air, it becomes mouldy and black because

Why does a dry cell becomes dead after a long time even if it has not been used?

Why pellets of potassium hydroxide become wet when exposed to air

If the diameter of Earth becomes two times its present value and its mass remains unchanged, the how would the weight of an object on the surface of the Earth be affected?

When caustic soda solution is kept in a glass bottle, the inner surface of the bottle becomes opaque. Explain.

A small air bubble exists inside a transparent cube of side 15 cm each. The apparent of the bubble observed from one face is 6 cm and from the opposite face its apparent distance becomes 4 cm. Determine the real distance of the bubble from the first face and refractive index of the material of the cube.