Homework Problem 7.53

[Rajiv Reddy 3K]

When finding the change in temperature of the solution involving zinc metal and hydrochloric acid solution, I didn’t understand why in the solutions manual, the specific heat of water is a negative value. I thought the specific heat value was always positive, and thus I ended up with a different final temperature than the one in the solutions (31 degrees Celsius). Any clarification would be appreciated, thanks!

[Anuk Burli 2C]

Hi

They're not saying the specific heat is negative they're using q system + q surroundings =0 so q system= - q surroundings so they just distributed the negative sign in q surroundings to the specific heat of water.