Q = smT
S water = 4.184 J/g℃
1 calorie = 4.184 J

How much heat, in joules and in calories, is required to raise the temperature of 2.0 L of water from 23 to 100 ℃? Remember, the density of water is 1.0 g/mL.

Explanation:

 Q=    MC  delta  T

M  = mass  =   density  x   volume(  2  x 1000= 2000ml)

M  =     1g/ml  x2000  ml  =  2000g

C  =  specific  heat   capacity =  4.18  g/c

delta  T  =  change  in  temperature  =  100 c (  boiling  point  of  water)   -  20 c =  80 c 

Q  is therefore  =   2000 g x 4.18 j/g c  x  80c  =  668800

it is b that is the answer.