The answer to your question is gravity. you are welcome. :-D
Answer: If a substance has a boiling point of 
then it is true that it will also change from a gas to a liquid at 78 °C while the gas loses energy.
Explanation:
The temperature at which vapor pressure of a liquid substance becomes equal to the atmospheric pressure is called boiling point of substance.
At the boiling point, liquid phase and vapor phase remains in equilibrium.
This means that as liquid phase changes into vapor phase and also vapor phase changes into liquid phase at the boiling point.
Thus, we can conclude that if a substance has a boiling point of then it is true that it will also change from a gas to a liquid at 78 °C while the gas loses energy.
Answer:
The atomic mass of the boron atom would be <em>10.135</em>
Explanation:
This is generally known as relative atomic mass.
Relative atomic mass or atomic weight is a physical quantity defined as the ratio of the average mass of atoms of a chemical element in a given sample to the atomic mass of 1/12 of the mass of a carbon-12 atom. Since both quantities in the ratio are masses, the resulting value is dimensionless; hence the value is said to be relative and does not have a unit.
<em>Note that the relative atomic mass of atoms is not always a whole number because of it being isotopic in nature.</em>
- <em>Divide each abundance by 100 then multiply by atomic mass</em>
- <em>Do that for each isotope, then add the two result. Thus</em>
Relative atomic mass of Boron = (18.5/100 x 11) + (81/100 x 10)
= 2.035 + 8.1
= 10.135
It is given that the person weighs 62 kg = 62,000 g
Natural abundances in mass percent are:
O = 65%
C = 18%
H = 10%
N = 3.0%
Ca = 1.6%
P = 1.2%
Corresponding weights of the elements are:
O = 65/100 * 62000 g = 40.30 * 10^3 g
C = 18/100 * 62000 g = 11.16 * 10^3 g
H = 10/100 * 62000 g = 62.00 * 10^2 g
N = 3.0/100 * 62000 g = 18.60 * 10^2 g
Ca = 1.6/100 * 62000 g = 9.92 * 10^2 g
P = 1.2/100 * 62000 g = 7.44 * 10^2 g
When a water vapor condenses, heat is being released from the process. This heat is called latent heat of vaporization since the phase change happens without any change in the temperature. This value is constant per mole of a substance as a function of pressure and temperature. For this problem, we are given the heat of vaporization at a certain T and P. We use this value to calculate the total heat released from the process. We calculate as follows:
Total heat released: 32.4 g ( 1 mol / 18.02 g ) (40.67 kJ / mol) = 73.12 kJ
Therefore, 73.12 kJ of heat is released from the condensation of 32.4 g of water vapor.
