Final answer:
To find the specific heat, use the formula c = Q / (m ⋅ ΔT). For an 18g sample that absorbs 75J and experiences a temperature rise from 15°C to 40°C, the specific heat is calculated to be 0.1667 J/g°C.
Step-by-step explanation:
To determine the specific heat of a material when an 18g sample absorbed 75J as it was heated from 15°C to 40°C, the formula for specific heat (c) which is c = Q / (m ⋅ ΔT) can be used, where Q is the amount of heat absorbed, m is the mass of the substance, and ΔT is the change in temperature. In this case, the change in temperature (ΔT) is 40°C - 15°C = 25°C, the mass (m) is 18g, and the heat absorbed (Q) is 75J.
Therefore, the specific heat (c) is calculated as follows:
c = 75J / (18g ⋅ 25°C)
c = 75J / (450g°C)
c = 0.1667 J/g°C
The specific heat capacity of the material is 0.1667 J/g°C.