How much heat, in joules and in calories, must be removed from 1.75 mol of water to lower its temperature from 25 degree celsius to 15 degree celsius?
You would need to remove
First, start by listing the specific heat of water in both calories per gram Celsius, and in Joules per gram Celsius.
A substance's specific heat will tell you how much energy you need to put in to increase the temperature of 1 gram of that substance by 1 degree Celsius.
Now, the relationship between heat added or removed and the change in temperature that consequently takes place is described by this equation
Since the equation uses grams, use water's molar mass to go from moles to grams
Now just plug your values into the equation and solve for
Rounded to two sig figs, the number of sig figs given for 25 and 15 degrees Celsius, the answers will be
SIDE NOTE The answers have a negative sign because heat is being lost by the system.