Explanation

The molar mass of CaCO₃ is approximately 100 g/mol.

The molar mass of calcium (Ca) in CaCO₃ is about 40 g/mol.

The proportion of calcium in CaCO₃ is  40/ 100 = 0.4

Therefore, in 0.1 g of CaCO₃, the amount of calcium is  0.1×0.4=0.04 g.

Explanation

The binding energy per nucleon is highest for intermediate-sized nuclei (e.g., iron).

Both lighter and heavier nuclei have lower binding energies per nucleon compared to these intermediate nuclei.

Explanation

Transistors primarily act as current amplifiers in a circuit.

They can increase the current flowing through a circuit, which can also be used for voltage amplification and switching.

Explanation

A moving charged particle is surrounded by both an electric field and a magnetic field.

The electric field is due to the charge itself, and the magnetic field is generated due to the particle's motion.

Explanation

Ohm × Farad is equivalent to a second (s).

This is because the unit of capacitance (Farad)

multiplied by resistance (Ohm) gives time (s),

which represents the time constant in RC circuits.

Explanation

When a soap bubble is charged, the repulsive forces between like charges on the surface of the bubble cause the bubble to contract, decreasing its size.

Explanation

Among the listed liquids, heptane (C₇H₁₄) has the greatest molecular weight

Thus the strongest intermolecular forces, lead to the lowest vapor pressure at the same temperature

Explanation

Ammonia (NH₃) has a higher boiling point than phosphine (PH₃)

Ammonia exhibits hydrogen bonding, a stronger intermolecular force than the dipole-dipole forces in phosphine.

Explanation

When a gas expands suddenly (an adiabatic expansion), it does work on the surroundings without any heat exchange.

As a result, the internal energy of the gas decreases, leading to a decrease in temperature.

Explanation

The Pauli exclusion principle states that no two electrons in an atom can have the same set of four quantum numbers.

This principle helps to explain the arrangement of electrons in atoms.