Question

Heat transfer between two substances is affected by specific heat and the

chemical composition of the substances.
state of matter of the substances at room temperature.
thermal equilibrium of the substances.
amount of time and area of physical contact between the substances.

Answer 1

All of the above. Each factor you listed affects heat transfer in some way:

- Specific heat and chemical composition: Chemical composition determines thermal properties (thermal conductivity, specific heat, density). Specific heat tells how much energy is required to change a substance’s temperature, so it affects how much heat is exchanged and how the temperatures change when heat flows.

- State of matter at room temperature: Solids, liquids and gases have very different thermal conductivities and allow different heat-transfer modes (conduction in solids, convection in fluids, etc.), so state of matter influences the rate and mechanism of heat transfer.

- Thermal equilibrium: Heat transfer requires a temperature difference. If two substances are already in thermal equilibrium (same temperature), there is no net heat transfer; otherwise heat flows until equilibrium is reached.

- Amount of time and contact area: For conduction, heat rate follows Fourier’s law (Q̇ = k A ΔT / L), so larger contact area and longer time increase total heat transferred (Q = Q̇ · t).

In short: temperature difference, material properties (including specific heat and composition), physical state, contact geometry (area, thickness) and time all matter; radiation and convective conditions also play roles.