200cal of heat is withdrawn from 10gm of water at 40℃ the resulring temp. Is
Answers
Answer:Problem Solving with Heat
Heat is quite a complex concept. Heat can be effected by how much of the substance there is,
what temperature the substance is at, and what the substance is. We need a unit define and
quantify heat. It is a unit that you are very familiar with already; the calorie.
Calories
A calorie is a unit of energy, of heat. With every substance having a different specific heat ca-
pacity, it can be difficult to come up with a unit that describes all energy. It was decided to pick
a common substance to act as a standard against which all other substances would be measured.
The common substance picked was water. We know that mass, specific heat, and temperature
all effect the energy of a substance so to keep the numbers very simple:
a calorie was defined as the amount of energy needed to raise 1 grams of water by 1 oC
Do you notice that all three aspects of heat are included; mass, temperature, and identity? Thus,
the specific heat capacity of water (as indicated in the previous section) is defined as 1 cal/goC.
So if 1 calorie of heat is applied to 1 gram of water at 20 oC, the water increases to 21 oC. If 10
calories of heat are applied to 1 gram of water at 20 oC, the water increases to 30 oC. If 10 calo-
ries of heat are applied to 10 grams of water at 20 oC, the water increase to 21 oC! Let’s put all
this into a simple equation which includes all of our variables:
Q = mc Tf—Ti)
Q = mc T)
The heat quantity is Q, the mass is m, the specific heat capacity is c, and the final temperature is
Tf while the initial temperature is Ti
.. Another way to represent this equation is by combining
Tf and Ti
into one variable T, which is the change in the temperature; the same thing as Tf-Ti
Explanation: