JEE Main levelSingle correct optionDifficulty 2 of 3td085
100mL of 1.00M HCl is mixed with 100mL of 1.00M NaOH in an insulated cup. For neutralisation ΔH=−57.1kJmol−1. Assuming density 1.00gmL−1, specific heat 4.18Jg−1K−1 and no heat loss to the cup, the temperature rise is
A6.83K
B13.66K
C3.42K
D0.68K
Answer: A
Moles of water formed =0.100×1.00=0.100mol, so q=0.100×57100=5710J. The mass heated is 200g, so ΔT=5710/(200×4.18)=6.83K.