Answer:
The change in internal energy is - 1.19 kJ
Explanation:
<u>Step 1:</u> Data given
Heat released = 3.5 kJ
Volume calorimeter = 0.200 L
Heat release results in a 7.32 °C
Temperature rise for the next experiment = 2.49 °C
<u>Step 2:</u> Calculate Ccalorimeter
Qcal = ccal * ΔT ⇒ 3.50 kJ = Ccal *7.32 °C
Ccal = 3.50 kJ /7.32 °C = 0.478 kJ/°C
<u>Step 3:</u> Calculate energy released
Qcal = 0.478 kJ/°C *2.49 °C = 1.19 kJ
<u>Step 4:</u> Calculate change in internal energy
ΔU = Q + W W = 0 (no expansion)
Qreac = -Qcal = - 1.19 kJ
ΔU = - 1.19 kJ
The change in internal energy is - 1.19 kJ
