Posted by ********tasha******** on Friday, March 9, 2012 at 12:07pm.

How many grams of water at 20.0C are necessary to change 800.0g of water at 90.0C to 50.0C

- physics help please -
**drwls**, Friday, March 9, 2012 at 12:17pm
You want to lower the temperature of the 800 g of 90 C water by 40 C, to 50 C. The heat loss from the hot water will be 800*50 = 40,000 calories, since the specific heat is C = 1.00 cal/(g*C)

The cold water that you add will also end up at 50 C after mixing, and it will have to lose 40,000 calories.

The mass M of cold water must be such that

M*C*30 = 40,000 calories

M = 1333 g

## Answer this Question

## Related Questions

- Physics - how many grams of water at 20 degrees celcius are necessary to change...
- Chemistry Physics - How many grams of water at 20°C are necessary to change 800g...
- Physics Science - How many grams of water at 20°C are necessary to change 800g ...
- Physics Science - How many grams of water at 20°C are necessary to change 800g ...
- Physics - A lukewarm bottle containing 800 grams of water is placed in a ...
- Physics - A lukewarm bottle containing 800 grams of water is placed in a ...
- Physics - A lukewarm bottle containing 800 grams of water is placed in a ...
- Physics - A lukewarm bottle containing 800 grams of water is placed in a ...
- chem - How much heat is necessary to change 5 grams of water at 10 degrees ...
- Chemistry - How much heat is necessary to change 5 grams of water at 10 degrees ...