Calorific value is measured in: MCQ with Answer and Explanation

Explanation:
Bakelite, the first fully synthetic plastic, is a thermosetting phenol formaldehyde resin. It is formed by a condensation reaction between phenol and formaldehyde. Once molded and heated, it sets permanently and cannot be remelted. It is used for electrical switches, utensil handles, and jewelry.

Explanation:
Graham's law of diffusion/effusion states that the rate of diffusion of a gas is inversely proportional to the square root of its molar mass. Lighter gases diffuse faster. This law helps in separating isotopes (e.g., ²³⁵U enrichment) and understanding gas behavior. Boyle's and Charles' deal with P-V-T relationships. Avogadro's deals with V and number of moles.

Explanation:
This is a single displacement reaction. Iron (Fe) is more reactive than Copper (Cu), so it displaces copper from its aqueous sulfate solution. The blue color of CuSO₄ fades, and a brown deposit of Cu forms. Reactivity series dictates that a more reactive metal displaces a less reactive one.