d. Oxygen

Explanation: Greenhouse gases, such as methane, water vapour, and carbon dioxide, trap heat in the Earth's atmosphere and contribute to the greenhouse effect. Oxygen, however, does not have this property. It is a major component of the atmosphere but does not significantly contribute to the greenhouse effect.

b. Nm^-2

c. 32

Explanation: The molecular weight of the gas is 2 × 32 = 64

c. nature of the material

Explanation: Thermal conductivity is a property intrinsic to the material itself, reflecting how well it can conduct heat.

b. f = r/2

b. volt/ohm

Explanation: According to Ohm's Law, I = V/R , where I is the current in amperes, V is the voltage in volts, and R is the resistance in ohms. Thus, an ampere can be represented as a volt divided by ohm, or V ohm^{− 1} Vohm⁻¹.

b. semiconductor

Explanation: In semiconductors, as temperature increases, more electrons gain enough energy to move from the valence band to the conduction band, resulting in an increase in charge carriers (electrons and holes). This leads to a decrease in resistivity.

a. α > β > γ.

Explanation: Alpha (α) particles have the highest ionizing power because they are large, heavy, and carry a +2 charge. Beta (β) particles, which are high-energy electrons, have moderate ionizing power, while gamma (γ) rays are high-energy electromagnetic waves and have the least ionizing power because they do not have mass or charge.

a. K

Explanation: Atomic radius increases as you move down a group in the periodic table because additional electron shells are added, making the atom larger. In this case, potassium (K) is below sodium (Na), lithium (Li), and hydrogen (H) in Group 1, so it has the largest atomic radius among them.

(a) Hydrogen chloride

Explanation: In hydrogen chloride, the bond between hydrogen and chlorine is a covalent bond, where electrons are shared between the two atoms. Sodium chloride (NaCl), lithium hydride (LiH), and calcium oxide (CaO) all involve ionic bonds, where electrons are transferred from one atom to another, leading to the formation of positive and negative ions.

a. CH₃COOH

Explanation: A weak electrolyte is a substance that only partially ionizes in solution. Acetic acid (CH₃COOH) is a weak acid and only partially dissociates into ions in water. In contrast, NaOH (sodium hydroxide), H₂SO₄ (sulfuric acid), and NaCl (sodium chloride) are strong electrolytes, meaning they fully dissociate into ions in aqueous solution.

b. P₂O₅

Explanation: Phosphorus pentoxide is a powerful desiccant that effectively absorbs water from gases, including ammonia.