Depression in freezing point (Δ
) =
×m×i,
where,
= cryoscopic constant =
,
m= molality of solution = 0.0085 m
i = van't Hoff factor = 2 (For
)
Thus, (Δ
) = 1.86 X 0.0085 X 2 =
Now, (Δ
) =
- T
Here, T = freezing point of solution
= freezing point of solvent =
Thus, T =
- (Δ
) = -
Answer: 10.9 mol.
Explanation:
- To understand how to solve this problem, we must mention the reaction equation where water produced from PbO₂.
Pb + PbO₂ + 2H₂SO₄ → 2PbSO₄ + 2H₂O
- Now, it is a stichiometric oriented problem, that 1 mole of PbO₂ produces 2 moles of H₂O.
Using cross multiplication:
1.0 mole of PbO₂ → 2.0 moles of H₂O
5.43 moles of PbO₂ → ??? moles of water
The moles of water produced = (5.43 x 2.0) = 10.86 moles ≅ 10.9 moles.
Answer:
natural selection
Explanation:
The process that results in changes to the genetic material of a population over time
one mole of P weights about 31 grams
in one mole there are 6.022*10^23 atoms
we use the rule of threes
6.022*10^23atoms......weight..........31 grams
3.45*10^23 atoms.........weight...........x grams
x=(3.45*10^23*31)/6.022*10^23
x=106.95/6.022=<u><em>17.76 grams</em></u>
