An ion M³⁺ has 10 electrons and 14 neutrons. The atomic number and mass number of M are: MCQ with Answer and Explanation

Explanation:
Plaster of Paris is calcium sulfate hemihydrate, CaSO₄·½H₂O. It is prepared by heating gypsum (CaSO₄·2H₂O) at 373 K. It sets with water to form gypsum.

Explanation:
Burning of magnesium ribbon produces a new substance, magnesium oxide (MgO), and releases heat and light, which are indicators of a chemical change. Melting, dissolving, and boiling are physical changes because the chemical composition remains unchanged. Chemical changes are generally irreversible.

Explanation:
Specific conductance (conductivity) is the conductance of a 1 cm³ solution. It decreases with dilution because the number of ions per unit volume decreases. Equivalent conductance is the conductance of all ions produced by 1 gram equivalent of electrolyte. It increases with dilution because the ions have more space to move, reducing interionic attractions.