We see from the chemical formula itself that there is 1
mole of F2 for every 1 mole of CaF2, hence the number of moles of CaF2 is also:
moles CaF2 = 1.23 moles
The molar mass of CaF2 is 78.07 g/mol, so the mass is:
mass CaF2 = 78.07 g / mol * 1.23 mol
<span>mass CaF2 = 96.03 grams</span>
The molecular mass of pyrene is 204.4 g/mol.
From;
ΔT = Kb m i
Where;
- ΔT = boiling point elevation
- Kb = boiling point constant
- m = molality
- i = Van't Hoff factor
Since the compound is molecular; i = 1
The number of moles of pyrene = 4.04 g/MM
Where; MM = molar mass of pyrene
molality = number of moles of pyrene/mass of solvent in Kg
The mass of solvent = 10 g or 0.01 Kg
molality = 4.04 g/MM/0.01
ΔT = Boiling point of solution - Boiling point of pure solvent
ΔT = 85.1°C - 80.1°C
ΔT = 5°C
5 = 2.53 × 4.04 g/MM/0.01 × 1
5 = 10.22 × 1/0.01 MM
0.05MM = 10.22
MM= 10.22/0.05
MM= 204.4 g/mol
Learn more: brainly.com/question/2292439
Answer:
If it loses an electron, it becomes positively charged and is known as a cation.
Explanation:
The potential energy ..
1- when a rubber band is stretche and waiting to be released
2- an acorn hanging from a oak tree
3- a pice of celery
The answer is catalyst.
A catalyst is characterized by acceleration the rate of a chemical reaction but not modifiy the equilibrium, which is what k represents (the constant of equilibrium of the reaction).
The catalyst manages that the reaction goes through a different pathway, with a lower activation energy, so the transition compound is reached faster and the whole reaction goes faster, but the final species and their equilibriium concentrations do not change.
