Explanation

The First Law of Thermodynamics states that energy can neither be created nor destroyed, only transformed from one form to another.

Hence, it is essentially the law of conservation of energy.

Explanation

Boyle’s Law: At constant temperature, pressure is directly proportional to density (P ∝ ρ).

This is because P ∝ 1/V, and since ρ = m/V, higher pressure means higher density for a fixed mass.

Explanation

PVC (Polyvinyl chloride) is a synthetic polymer made from repeating vinyl chloride monomers.

CH₄, SO₂, and CO₂ are simple molecules, not polymers.

Explanation

Salt (solute) dissolves in water (solvent) to form a homogeneous mixture called a solution.

The salt ions spread evenly throughout the water, making it uniform.

Explanation

Calcium carbonate + hydrochloric acid → calcium chloride (CaCl₂), water (H₂O), and carbon dioxide (CO₂).

This is a neutralization + decomposition type reaction of an acid with a carbonate.

Explanation

Viscosity means resistance to flow; lower viscosity = flows more easily.

Acetone is less viscous than water, glycerine, and ethyl alcohol, so it flows fastest.

Explanation

Argon is a noble (inert) gas found in Group 18 of the periodic table; it is chemically unreactive.

H₂ and O₂ are reactive gases.

Explanation

In plants, xylem mainly transports water and minerals upward.

Phloem carries organic food and minerals both upward and downward, enabling downward translocation.

Explanation

Prophase involves chromosome condensation and spindle formation, which takes the most time.

It is the longest stage of mitosis.

Explanation

ZTBL stands for Zarai Tarqiati Bank Limited

Founded: 1961

Headquarters: Islamabad