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Specific Heat. Specific Heat (c, sometimes s, but usually c) Things heat up or cool down at different rates. Land heats up and cools down faster than water, and aren’t we lucky for that!?.
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Specific Heat (c, sometimes s, but usually c) Things heat up or cool down at different rates. Land heats up and cools down faster than water, and aren’t we lucky for that!?
Specific heat is the amount of heat required to raise the temperature of 1 kg of a material by one degree (C or K, they’re the same size). C water = 4184 J / kg C (“holds” its heat) C sand = 664 J / kg C (less E to change) This is why land heats up quickly during the day and cools quickly at night and why water takes longer.
Why does water have such a high specific heat? water metal Water molecules form strong bonds with each other in a water molecule; so it takes more heat energy to break the bonds. Metals have weak bonds and do not need as much energy to break them.
WHERE’S THE MATH, MATE?! Q = m x T x Cp Q= change in thermal energy m = mass of substance T = change in temperature (Tf – Ti) Cp= specific heat of substance
Specific Heat Capacity If 25.0 g of Al (Specific heat = 897c) cool from 310 oC to 37 oC, how many joules of heat energy are lost by the Al? Q = m x T x Cp Solution: Q = 25*(37-310)*897 Q= 25*(-273)*897 Q= -6122025 J Notice that the negative sign on q signals heat “lost by” or transferred OUT of Al.