Answer:
[KBr] = 454.5 m
Explanation:
m is a sort of concentration that indicates the moles of solute which are contianed in 1kg of solvent.
In this case, the moles of solute are 0.25 moles.
Let's determine the mass of solvent in kg.
Density of heavy water, solvent, is 1.1 g/L and our volume is 0.5L.
1.1 g = mass of solvent / 0.5L, according to density.
mass of solvent = 0.5L . 1.1g/L = 0.55 g
We convert the mass to kg → 0.55 g . 1kg /1000g = 5.5×10⁻⁴ kg
m = mol/kg → 0.25 mol /5.5×10⁻⁴ kg = 454.5 m
Answer:
900 J/mol
Explanation:
Data provided:
Enthalpy of the pure liquid at 75° C = 100 J/mol
Enthalpy of the pure vapor at 75° C = 1000 J/mol
Now,
the heat of vaporization is the the change in enthalpy from the liquid state to the vapor stage.
Thus, mathematically,
The heat of vaporization at 75° C
= Enthalpy of the pure vapor at 75° C - Enthalpy of the pure liquid at 75° C
on substituting the values, we get
The heat of vaporization at 75° C = 1000 J/mol - 100 J/mol
or
The heat of vaporization at 75° C = 900 J/mol
207 is the mass number. 82 would be the atomic number
<span>1=H, 2=B, 3=F, 4=A,5=C,6=E, 7=D, 8=G
</span>9: 69Ga=60.12% and 71Ga=39.88%; total=69.797amu
10: 27 27.977 92.23; 28 28.976 4.67; 29 29.974 3.10; abundance =28.07 Silicon
I hope this helps!
