the number of joules needed to raise the temperature of 10 grams of water from 20 degrees celsius to 30 degrees celsius is

It takes 1 calorie to raise temp of 1 gram of water by 1° C so

10 calories will raise 10 grams of water by 1°. Thus 100 calories

are needed to raise 10 grams of water by 10° C from 20° to 30°

Now 1 calorie = 4.184 J so multiply the 100 calories by 4.184 to

determine that 418.4 Joules of energy are needed to complete the task