Answer:
29.4855 grams of chlorophyll
Explanation:
From Raoult's law
Mole fraction of solvent = vapor pressure of solution ÷ vapor pressure of solvent = 457.45 mmHg ÷ 463.57 mmHg = 0.987
Mass of solvent (diethyl ether) = 187.4 g
MW of diethyl ether (C2H5OC2H5) = 74 g/mol
Number of moles of solvent = mass/MW = 187.4/74 = 2.532 mol
Let the moles of solute (chlorophyll) be y
Total moles of solution = moles of solute + moles of solvent = (y + 2.532) mol
Mole fraction of solvent = moles of solvent/total moles of solution
0.987 = 2.532/(y + 2.532)
y + 2.532 = 2.532/0.987
y + 2.532 = 2.565
y = 2.565 - 2.532 = 0.033
Moles of solute (chlorophyll) = 0.033 mol
Mass of chlorophyll = moles of chlorophyll × MW = 0.033 × 893.5 = 29.4855 grams
Answer:In the decades prior to 1993 there was a robust Pacific herring population in Prince William Sound (PWS). Not only are these forage fish a key link in the complex food web of PWS, but they supported a lucrative early-season commercial fishery that brought the communities of the Sound to life each spring. By 1994, that fishery was closed and only briefly reopened for two years in the late 1990s. The current, approximately 10,000-ton biomass, is tiny compared to the peak value of 130,000 tons or the long-term average prior to the collapse of around 65,000 ton.
Explanation:
Answer:
P = 1333.33 N
Explanation:
The pressure exerted by the boy on the floor can be calculated by the following equation:

where,
P = Pressure exerted by the boy = ?
F = Force Applied = Weight of Boy = 40 kg = 40 N (since 1 kg = 1N)
A = Area of application of force = 2(Area of one show) = 2(6 cm x 25 cm)
A = 2(0.06 m x 0.25 m) = 0.03 m²
Therefore,

<u>P = 1333.33 N</u>