Question

30.0 g H₂O at an unknown temperature is mixed with 27.0 g of water at 15.8°C in a coffee-cup

calorimeter. If the final temperature of the mixture is 29.1°C, what is the initial temperature of the
water?

Answer 1

Step-by-step explanation:

The added water is hotter than the coffeecup water because the final temp is higher.....

sooooo......

heat lost by the 30 g hot water = heat gained by 27 g cooler water

30.0 g * 4.182 j/g * ( Ti- 29.1)C = 27.0 g * 4.182 j/g * ( 29.1 - 15.8 ) C

30 * (Ti - 29.1) = 27 ( 29.1 - 15.8 ) <=====solve for Ti

Ti = 41.1 C <===== ( to three signif dig)