110 g of water (specific heat = 4.184 J/g C) and 100 g of a metal sample (specific heat = 0.397 J/g C) are heated from 25 degrees C to 75 degrees C. Which substance required more thermal energy?

Water.

Explanation:

The thermal energy required to heat an object is calculated from the relation:

Q = m. C.ΔT, where,

Q is the thermal energy,

m is the mass of the substance,

C is the specific heat of the substance,

ΔT is the increase in temperature.

For water,

Q for water = m. C.ΔT = (110 g) (4.184 J/g.°C) (75 °C - 25 °C) = 23012 J.

For the substance,

Q for the substance = m. C.ΔT = (100 g) (0.397 J/g.°C) (75 °C - 25 °C) = 1985 J.

So, it is clear that water (23012 J) requires more thermal energy than the substance (1985 J).