Question

You computed the specific heat for each of the four metals using the formula below:

C metal equals StartFraction negative C water m water delta T water over m metal delta T metal EndFraction.

Check all items that you used, either directly or indirectly, each time you did this computation.

the first law of thermodynamics (heat lost by a metal equals the heat gained by the water)

the ability of heat to flow from a hot object to a cooler one

masses for the metal and the water in the calorimeter

temperature changes for the water and the metal

the known specific heat of the water

Answer 1

All five items were used. Brief justification for each:

- The first law of thermodynamics: Yes — you set heat lost by the metal equal to heat gained by the water to derive the equation.
- The ability of heat to flow from a hot object to a cooler one: Yes — you assume the metal is hotter and transfers heat to the cooler water, which is why ΔT signs and the negative sign are applied.
- Masses for the metal and the water in the calorimeter: Yes — m_metal and m_water appear explicitly in the formula.
- Temperature changes for the water and the metal: Yes — ΔT_water and ΔT_metal appear explicitly and are measured.
- The known specific heat of the water: Yes — C_water is used in the numerator as the reference specific heat.