Atomic number is equal to the number of protons and electrons
Atomic mass - protons = neutrons
protons + neutrons = atomic mass
I hope this helps
Given:
Amount of heat produced = 100 kcal per hour
Let's find the rate of energy production in joules.
We know that:
1 calorie = 4.184 Joules
1 kcal = 4.184 Joules
To find the rate of energy production in Joules, we have:

Therefore, the rate of energy production in joules is 418.4 kJ/h which is equivalent to 418400 Joules
ANSWER:
418.4 kJ/h
Answer: The final temperature is 470K
Explanation: Using the relation;
Q= ΔU +W
Given, n = 2mol
Initial temperature T1= 345K
Heat =Q= 2250J
Workdone=W=-870J(work is done on gas)
T2 =Final temperature =?
ΔU =3/2nR(T2-T1)
ΔU=3/2 × 2 ×8.314 (T2 - 345)
ΔU=24.942(T2-345)
Therefore Q = 24.942(T2-345)+ (-870)
2250=24.942(T2-345)+ (-870)
125.09=(T2-345)
T2 =470K
Therfore the final temperature is 470K
Answer:
The needed energy to melt of ice is 1670 J.
Explanation:
Given that,
Mass of ice = 5 g
Specific latent heat = 334000 J/kg
We need to calculate the energy
Using formula of energy

Where, m = mass
L = latent heat
Put the value into the formula


Hence, The needed energy to melt of ice is 1670 J.
This topic is actually quite controversial, but the answer in this case would be C.
Just some food for thought, the 2nd law of thermodynamics entropy of the universe is always increasing, but that doesn't necessarily mean that earth's entropy has to. As long as the net change in entropy of the universe is increasing it doesn't matter if one planet is decreasing a nominal amount. Next, Earth as said is not a closed system and you could argue that the sunlight and energy from the sun is increasing the total energy within the system that is earth meaning that it is increasing in entropy. Next, if you consider increasing entropy as an increase in the number of possible permutations that the universe or parts of the universe can take, then it is completely possible that an ordered planet and life is possible, although rare. This theory explains why there are so many life forms and why entropy is actually increasing when divergent evolution occurs.