Question

Please show me how to do a question like this.

Answer 1

Answer:

$41.8\text{ KJ}$

Explanation:

Here, we want to get the amount of heat needed

Mathematically, we use the formula below:

$\begin{gathered} Q\text{ = C}_p\text{ }\times m\text{ }\times\Delta T \\ Q\text{ = amount of heat} \\ C_p\text{ = specific heat capacity = 4.18 J/g}\degree C \\ m\text{ = mass = 200g} \\ \Delta T\text{ = change in temperature = 90-40 = 50}\degree C \end{gathered}$

Now, we proceed to substitute the values as follows:

$Q\text{ = 4.18 }\times200\text{ }\times50\text{ = 41800 J = 41.8 KJ}$