Answer:
3.11 mol/kg
Explanation:
Molality M = number of moles of solute, n/mass of solvent, m
To calculate the number of moles of glycerol (C₃H₈O₃) in 22.75 g of glycerol, we find its molar (molecular) mass, M',
So, M' = 3 × atomic mass of carbon + 8 × atomic mass hydrogen + 3 × atomic mass of oxygen
= 3 × 12 g/mol + 8 × 1 g/mol + 3 × 16 g/mol = 36 g/mol + 8 g/mol + 48 g/mol = 92 g/mol.
So, number of moles of glycerol, n = m'/M' where m' = mass of glycerol = 22.75 g and M' = molecular mass of glycerol = 92 g/mol
So, n = m'/M'
n = 22.75 g/92 g/mol
n = 0.247 mol
So, the molality of the solution M = n/m
Since m = mass of ethanol = 79.6 g = 0.0796 kg, substituting the value of n into the equation, we have
M = 0.247 mol/0.0796 kg
M = 3.11 mol/kg
So, the molality of the solution is 3.11 mol/kg.
Answer:
Electrical energy (form of kinetic energy)
Explanation:
Your answer is <span>D) The angle of light from the sun as it reflects off the moon and viewed from the Earth's surface because of the way the sun hits the moon one side has to light the other doesn't and when the moon rotates the sun hits another part of the moon.
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Answer:
Malleability is intensive
Length is extensive
Hardness is intensive
Volume is extensive
Explanation:
Extensive properties change when u change the size of an object and intensive properties don’t
Also I just took the quiz
Answer:
1) The hydrogen-ion concentration is 0.001 M and pH of the solution is less than 7 which means that the solution is acidic.
2) The acid dissociation constant of a weak monoprotic acid is .
Explanation:
1) Concentration of hydroxide ions =
The pOH of the solution:
pH + pOH = 14
pH = 14 - pOH = 14 - 11 = 3
The pH of the solution is given as:
The hydrogen-ion concentration is 0.001 M and pH of the solution is less than 7 which means that the solution is acidic.
2)
Dissociation on weak monoprotic weak acid is given by :
Initially
0.5 M 0 0
At equilibrium
(0.5-x) x x
Given , hydrogen ions concentration =
The expression of a dissociation constant is given as:
The acid dissociation constant of a weak monoprotic acid is .