A solution turns blue litmus red. The solution is: MCQ with Answer and Explanation

Explanation:
Covalent compounds consist of molecules held together by weak van der Waals forces, unlike the strong electrostatic forces in ionic lattices. Therefore, less heat energy is required to break these intermolecular forces, resulting in low melting and boiling points. Both statements are true and R correctly explains A.

Explanation:
Single superphosphate (SSP) is manufactured by treating rock phosphate with sulfuric acid. The resulting product is a mixture of calcium dihydrogen phosphate (Ca(H2PO4)2), which is the actual fertilizer providing soluble phosphorus, and calcium sulfate (CaSO4, gypsum), which is an inactive filler.

Explanation:
Isotopes are atoms of the same element (same atomic number, same number of protons) but different mass numbers due to varying number of neutrons. For example, ¹²C, ¹³C, ¹⁴C. Their chemical properties are similar but physical properties (mass, density, rate of diffusion) differ. Isobars have same mass number but different atomic numbers.