a) Volume percent
Formula: % v/v = [volume solute / volume solution] * 100
Just to make it easy take a base of 50 volume parts of ethylen glycol and 50 volume parts of water to make 100 volumes of mixture (this assumpion will be valid for all the questions):
% v/v =[ 50 ml ethyleneglycol] / [100 ml mixture] * 100 = 50%
Answer: 50% v/v
b) Mass percent
% m/m = [mass ethylene glycol / mass solution] * 100
mass ethylene glycol = 50 ml * 1.114 g/ ml = 55.7 g
mass of mixture = 100 ml * 1.07 g/ml = 107 g
% m/m = [55.7 / 107 g] * 100 = 52.06 %
Answer: 52.06%
c) Molarity
M = number of moles of solute / liters of solution
number of moles of solute = mass in grams / molar mass
number of moles of ehtylene glycol = 55.7 g / 62.07 g/mol = 0.8974 mol
liters of solution = 0.1 liter
M = 0.8974 mol / 0.1 liter = 8.974 M
Answer: 8.974 M
d) Molality
m = number of moles of solute / kg of solvent
number of moles of ethylen glycol = 0.8974 mol
mass of water = 50 ml * 1 g/ml = 50 g = 0.05 kg
m = 0.8974 mol / 0.05 kg = 17.95 m
Answer: 17.95 m
e) mole fraction
mole fraction = [number of moles of solute] / [number of moles of mixture] * 100
number of moles of ethylen glycol = 0.8974 mol
number of moles of water = 50 g / 18.01 g /mol = 2.776 mol
mole fraction = 0.8974 mol / [0.8974 mol + 2.776 mol] = 0.244
Answer: 0.244
Answer:
Because X-rays have wavelengths similar to the size of atoms
Answer:
B
Explanation:
The tendency of a liquid to convert to vapour increases smoothly with increasing temperature. Vapour pressure shows the tendency of a liquid to convert to vapour. Increase In vapour pressure shows an increased tendency to convert to vapour. The higher the temperature, the higher the vapour pressure.
Answer:
Starting from the top
1.498
1.18
43.5
51.3
For step 7
2.498
1.27
40.5
51.4
For 8
3.498
1.37
37.5
51.4
For 9
4.498
1.47
35.0
51.5
Lmk if anyone needs earlier steps, but I'm going to assume no since you're already on 6
Explanation:
Answer:
The blue star is the hottest star.
Explanation:
Red stars are cooler than the sun, with surface temperatures of 3,500 K for a bright red star and 2,500 K for a dark red star. The hottest stars are blue, with their surface temperatures falling anywhere between 10,000 K and 50,000 K
