# If 200 grams of water is to be heated from 24°C to 100°C to make a cup of tea, how much heat must be added?

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The specific heat of water is 4.18 #J# #/# #g*C# .

The specific heat of water is 4.18

##### 1 Answer

#### Explanation:

As you know, a substance's specific heat tells you how much heat is required to increase the temperature of

In water's case, you know that its specific heat is equal to

How much heat would you need to increase the temperature of

Well, if you need **per** gram to increase its temperature by **times more heat** to get this done.

Likewise, if you were to increase the temperature of **times more heat** than when increasing the temperature of

Combine these two requirements and you get the total amount of heat required to increase the temperature of

Mathematically, this is expressed using the following equation

#color(blue)(q = m * c * DeltaT)" "# , where

*final temperature* minus *initial temperature*

Plug in your values to get

#q = 200 color(red)(cancel(color(black)("g"))) * 4.18"J"/(color(red)(cancel(color(black)("g"))) color(red)(cancel(color(black)(""^@"C")))) * (100 - 24)color(red)(cancel(color(black)(""^@"C")))#

#q = "63536 J"#

I'll leave the answer rounded to two sig figs and expressed in *kilojoules*

#q = color(green)("64 kJ")#