# It takes 80 cal/g to change solid water at 0°C to liquid water. How many calories will it take to change 3 g of water at 0 °C to liquid water?

##### 1 Answer

#### Explanation:

The idea here is that the problem is providing you with a measure of how much heat is needed **per gram** of solid water, i.e. of *ice*, in order for a solid

Simply put, you are given a measure of how much heat is required to melt

So, you can say that **for every** **of ice** to convert it from solid at

This means that

#3 color(red)(cancel(color(black)("g"))) * "80 cal"/(1color(red)(cancel(color(black)("g")))) = color(darkgreen)(ul(color(black)("240 cal")))#

I'll leave the answer rounded to two **sig figs**, but don't forget that you only have one significant figure for the mass of ice.

So remember this notation

#color(blue)("80 cal")color(red)("/g") " "=" " color(blue)("80 cal")color(white)(.)color(red)("g"^(-1))#

means that **every** **of ice** at