Q: A
according to this formula, we can get the mole fraction of water (n):
P(solu) = n Pv(water)
when we have Pv(solu) = 22.8 and Pv(water) = 23.8 so by substitution:
22.8 = n * 23.8
n= 0.958
- we need to get the moles of glucose:
moles of water = 500 g(mass weight) / 18 (molar weight)= 27.7 mol
n = moles of water / ( moles of water + moles of glucose)
0.958 = 27.7 / ( 27.7+ moles of glucose)
0.958 moles of glucose + 26.5 = 27.7
0.968 moles of glucose = 1.2
moles of glucose = 1.253 mol
∴ the mass of glucose = no.of glucose moles x molar mass
= 1.253 x 180 = 225.5 g
Q: B
here we also need to get n (mole fraction of water )by using this formula:
Pv(solu) = n Pv(water)
when we have Pv(solu)=132 & Pv(water)=150 so, by substition:
132= n * 150
n = 0.88
so, mole fraction of solution = 1 - 0.88 = 0.12
and we can get after that the moles of water = (mass weight / molar mass)
- no.moles of water = 85 g / 18 g/mol = 4.7 moles
- total moles in solution = moles of water / moles fraction of water
= 4.7 / 0.88 = 5.34 moles
∴ moles of the solution = total moles in solu - moles of water
= 5.34 - 4.7 = 0.64 moles solute
∴ the molar mass of the solute = mass weight of solute / no.of moles of solute
= 53.8 / 0.64 = 84 g/mole
Q: C
moles of urea (NH2)2 CO = mass weight / molar mass
= 4.49 g / 60 g /mol
= 0.07 mol
moles of methanol = mass weight / molar mass
= 39.9 g / 32 g/mol = 1.25 mol
moles fraction of methanol = moles of methanol / (moles of methanol + moles of urea )
moles fraction of methanol = 1.25 / ( 1.25+0.07) = 0.95
by substitution in Pv formula we will be able to get the vapour pressure of the solu :
Pv(solu) = n P°v
Pv(solu) = 0.95 * 89 mm Hg
∴Pv(solu) = 84.55 mmHg
Answer:
Hence the concentration of a MnO41- solution that has absorbance of 0.490 in the same cell at that wavelength is 0.3266.
Explanation:
Now A = el, el=const
Then,
Answer:
3. Inverse 1. Direct
Explanation:
P- pressure
V - volume
T - temperature
P1*V1 / T1 = P2*V2 / T2 ...... (1)
That's the general gas law with the combined ideas of charles, boyle & lussac.
Whenever you are restricted as "constant" temperature, volume, or pressure...cancel them off of your equation.
in this case 3. is indirectly telling us to cancel the temperature (T).
so we'll be left w P1*V1 = P2*V2
now notice that any relation ship that is multiplied like the one above consists of inversely related quantities. & so we conclude that-
P & V are inversely proportional or have an inverse relationship.
similarly in 1. we'll cancel p off of the general formula (1)
to be left with V1/T1 = V2/T2
also note that quantities involved in division are directly related to each other & hence the answer.
Denser salt water makes the eggs to float in the water.
<u>Explanation:
</u>
Egg will always sink in water, as egg is denser than water.
But we can make it to float by means of adding excess salt to the water. Adding more salt to water makes it as denser than egg. Denser water makes less dense egg to float in water.
So, making the water as denser one leads to the floating of egg in the water.
Answer:
A five-sided shape is called a pentagon.
Explanation:
Answered by NONE other than the ONE & ONLY #QUEEN herself aka #DRIPPQUEENMO!!!
Hope this helped!!!
