1023 molecules or atoms depending on substance
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
4 Hydrogen Atoms should be correct. Because the 4 infront of it signifies the amount of hydrogen. It would also be 4 hydrogen atoms if it were written as H4N3, because the 4 is still around the H (as long as the 4 is under scored)
Protons: 12
Neutrons: 13
<span>Electrons: 12</span>
Answer:
P' = 41.4 mmHg → Vapor pressure of solution
Explanation:
ΔP = P° . Xm
ΔP = Vapor pressure of pure solvent (P°) - Vapor pressure of solution (P')
Xm = Mole fraction for solute (Moles of solvent /Total moles)
Firstly we determine the mole fraction of solute.
Moles of solute → Mass . 1 mol / molar mass
20.2 g . 1 mol / 342 g = 0.0590 mol
Moles of solvent → Mass . 1mol / molar mass
60.5 g . 1 mol/ 18 g = 3.36 mol
Total moles = 3.36 mol + 0.0590 mol = 3.419 moles
Xm = 0.0590 mol / 3.419 moles → 0.0172
Let's replace the data in the formula
42.2 mmHg - P' = 42.2 mmHg . 0.0172
P' = - (42.2 mmHg . 0.0172 - 42.2 mmHg)
P' = 41.4 mmHg
