The reaction is actually endothermic because delta H is positive, indicating that it absorbing heat.
The joules required to heat 2L of water in a pot from 20 c to the boiling point of water is calculated using the following formula
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 = 668800j
It has 7 electrons, 7 protons and 7 neutrons
