Now, a calorimeter is just a container, usually insulated against heat loss, that contains a liquid with a given heat capacity. We're going to say usually when a heated object is placed in a liquid, both the liquid and the container that it's in will absorb this released heat. And we're going to say here that our standard heat capacity, which is capital C for a calorimeter, it's just the amount of heat required to change its temperature.
Now the weight of the calorimeter is usually unknown, so we're going to exclude it from our mass in terms of the formula. Now standard heat capacity equals C=Q/ΔT, which is our heat divided by change in temperature. Our standard heat capacity is usually in units of Joules over degrees Celsius. Now this temperature could be given to us in Kelvin and if it is given to us in Kelvin, then the temperature must be converted to Kelvin as well.
The units here both have to match one another. Here Q, which is our heat, can be in Joules or in Kilojoules, so always be on the lookout for that too. Make sure your units all match so that they cancel out to isolate the missing variable.