Answer:
THE MOLAR MASS OF THE UNKNOWN MOLECULAR SUBSTANCE IS 200 G/MOL.
Explanation:
Mass of the unknown substance = 0.50 g
Freezing point of the solution = 3.9 °C
Freezing point of pure benzene = 5.5 °C
Freezing point dissociation constant Kf = 5.12°C/m
First, calculate the temperature difference between the freezing point of pure benzene and the final solution freezing point.
Change in temperature = 5.5 -3.9 = 1.6 °C
Next is to calculate the number of moles or molarity of the compound that dissolved.
Using the formula:
Δt = i Kf m
Assume i = 1
So,
1.6 °C = 1 * 5.12 * x/ 0.005 kg of benzene
x = 1.6 * 0.008 / 5.12
x = 0.0128 / 5.12
x = 0.0025 moles.
Next is to calculate the molar mass using the formula, molarity = mass / molar mass
Molar mass = mass / molarity
Molar mass = 0.50 g /0.0025
Molar mass = 200 g/mol
Hence, the molar mass of the unknown compound is 200 g/mol
Answer:
D.) 2,000 kilocalories would be the correct answer.
Explanation:
2Na+MGF2=2NAF+MG
I hope that's right :)
Answer:
χsolvent = 1.0000 - 0.1000 = 0.9000
Use Raoult's Law:
Psolution = (χsolvent) (P°solvent)
x = (0.900) (25.756)
x = 23.18 mmHg (to four sig figs)
A. electron, B. Nucleus
Proton is positive charge, electron is negative charge
proton weight, 1 AMU