**The specific heat of water is 1.0 cal/g°C. How much energy is required to raise the temperature of 25.1 g of water by 72.0 degree Celsius?**

Becky-
Follow these steps.
**What is the unknown?**Your problem asks "How much energy...?" The units aren't specified, but since you spot 'calories' in the given information, it will probably be easiest to get your answer in calories.**What information is given?**You know that:- the specific heat is 1.0 cal/g°C
- the mass of water is 25.1 g
- the temperature change is 72.0°C

**How is the information in the problem related to the unknown?**The relationship between heat and temperature change isheat = mass × specific heat × temperature change

**Do the math.**Now you're ready to do the calculation itself:heat = (25.1 g)(1.0 cal/g°C)(72.0°C)

**Is the final answer in the correct units?**You want only calories. All other units should 'cancel' in the calculation somewhere.**Is the size of the answer reasonable?**Your reasoning should go something like this: The specific heat means that it takes 1.0 calories of heat to warm 1 g of water up by 1°C. So it should take 25.1 calories to warm up 25.1 g of water by 1°C. And it should take 72.0×25.1 calories to warm up 25.1 g of water by 72.0°C.You can also check the answer by working the problem backwards. For example, take the calories just calculated and divide them by the temperature change and the grams of water; do you get a specific heat of 1.0 cal/g°C?

General Chemistry Online! How can I calculate the energy required to cause a temperature rise?

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Last Revised 08/17/15.URL: http://antoine.frostburg.edu/chem/senese/101/thermo/faq/print-energy-required-for-temperature-rise.shtml