Which of the following reactions will lead to the largest temperature change in the calorimeter?

Question

Which of the following reactions will lead to the largest temperature change in the calorimeter?

a

25 mL of 2 M NaOH added to 20 mL of 2 M HCI

b

50 mL of 1 M NaOH to 25 mL of 1 M HCI

c

25 mL of 2 M NaOH added to 50 mL of 2 M HCI

d

​50 mL of 1 M NaOH to 40 mL of 1 M HCI

Answer 1

a

25 mL of 2 M NaOH added to 20 mL of 2 M HCI -> 50 mmol NaOH + 40 mmol HCl -> 40 mmol H2O

b

50 mL of 1 M NaOH to 25 mL of 1 M HCI -> 50 mmol NaOH + 25 mmol HCl -> 25 mmol H2O

c

25 mL of 2 M NaOH added to 50 mL of 2 M HCI -> 50 mmol NaOH + 100 mmol HCl -> 50 mmol H2O

d

​50 mL of 1 M NaOH to 40 mL of 1 M HCI -> 50 mmol NaOH + 40 mmol HCl -> 40 mmol H2O

Since the most moles (mmoles) of H2O is formed in reaction (c), it would produce the greatest temperature change.