Can anyone help me with science equations?

Question

Calculate the thermal energy that must be transferred to raise the temperature of 5kg of ice from -20C to -10C.

Iamgiven two equations to choose from.

Q=(m)(C)(delta T) or Q=(L)(m)

I am not sure which one and I dont know where to insert the numbers.

CAn anyone just explain to me what to do.You dont have to give me the answer?

Answer 1

The whole approach of using equations for stuff like this is sub-optimal.  It is better to understand the physics of the situation: the heat capacity of a substance (which you usually have to look up) is the ratio between the number of calories added per unit mass and the change in temperature.  For ice, it is about 0.5 calorie per gram per degree C.

Answer 2

The first equation is the correct equation.  You have the mass and can easily find ∆T.  All you need is to look up the heat capacity or specific heat of ice. Insert that for C and calculate.  Make sure your dimensions are consistent.