Answer:
The mole fraction of benzene if 0.43
Explanation:
Let's apply the colligative property of vapor pressure lowering.
P° - Ps = P° . Xm
Where P° is vapor pressure of pure solvent
Ps is vapor pressure of solution
Xm is mole fraction of solute
Determine the solute and the solvent:
Solute: Toluene
Solvent: Benzene (Vapor pressure of pure bencene at 20°C, is 74.7Torr)
74.7 Torr - 32 Torr = 74.7 Torr . Xm
42.7 Torr / 74.7 Torr = 0.57 → Xm
Sum of mole fraction = 1
Mole fraction of bencene + Mole fraction of toluene = 1
Mole fraction of bencene + 0.57 = 1 ⇒ 1 - 0.57 = 0.43
<span>d. the synthesis of new chemicals by chemists.
New drugs are likely synthetic and made in the lab, not derived from existing organisms.</span>
Answer:
The air moves to the low pressure system creating wind.
Hope this helps! :)
<span><span>Convert the percentages into decimals (you can do that by dividing the percent by 100), then multiply that by its
corresponding mass to find its relative amount/ contribution to the
atomic mass of chromium. After doing so, add all of the obtained values
together to get the average mass.
</span>
83.79% = .08379
9.50% = .095
4.35% = .0435
2.36% = .0236
Average mass of chromium = 0.8379(51.94) + 0.095( 52.94) + 0.0435(49.95) + 0.0236(53.94)
Answer: 52amu
P.S. never forget units
</span>