Answer:

Explanation:
Hello,
In this case, for the computation of the energy loss when the cooling process is carried out, we use the shown below equation:

Whereas we need the mass, specific heat and change in temperature of iron within the process. Thus, the only value we need is the specific heat that is 0.444 J/(g°C), therefore, we compute the heat loss:

Negative sign points out the loss due to the cooling.
Regards.
Answer:
Density is defined as how tightly or loosely packed a substance is, or to the number of things or people in a certain area.
PbCl2 and PbCl4
Empirical formula is when the molecular formula is reduced (each element) by the same number until you are unable to do so any further.
CH2O cannot be further reduced, but C3H6O3 can all be divided by 3 making it CH2O (same empirical formula)
Answer:
A.
Explanation:
if it's the same element the protons will always be the same, but have different neutrons, and neutrons is made up of protons and atomic mass, which atomic mass numbers can be calculated different where in return gives different numbers of neutrons.
EX: say the element is carbon, carbon has 6 protons and that won't change, but carbon can have an atomic mass of 12, 13, or 14, etc. so when you make up the neutrons you add protons and atomic mass, 6 + 12 = 18 N
6 + 13 = 19 N
6 + 14 = 20 N