Answer: 20.7 kJ
Explanation:
According to first law of thermodynamics:
=Change in internal energy
q = heat absorbed or released
w = work done or by the system
w = work done on the system=
{Work is done on the system is positive as the final volume is lesser than initial volume}
w = 4.51 kcal =
(1kcal = 4.184kJ)
q = +1.79 kJ {Heat absorbed by the system is positive}

Thus
for a system that receives 1.79 kJ of heat from surroundings and has 4.51 kcal of work done on it at the same time is 20.7 kJ
Answer:
Hope this helps
Explanation:
https://seagrant.whoi.edu/wp-content/uploads/2018/05/ESTIMATING-POPULATION-SIZE-1.pdf
Answer: A. It can identify the elements in the sample.
Explanation: on edge
Answer:
Explanation:
The positive (protons) and negative (electrons) charges balance each other in a neutral atom, which has a net zero charge. Because protons and neutrons each have a mass of 1, the mass of an atom is equal to the number of protons and neutrons of that atom.