Solution :
We know that :
and 
Then,
..................(1)
Where,
= amount of solvent (in kg)
= amount of solute (in kg)
= molar mass of solute (g/mole)
= molality of solution (mole/kg)
Given :
=
, 


= 0.250 kg,
= 24.3 g
Then putting this values in the equation is (1),


g/mole
So, the molar mass of the unknown compound is 158.49 g/mole.
What do you mean by this?
Answer:
Protons and neutrons are made up of smaller subatomic particles. When protons or neutrons get close enough to each other, they exchange particles (mesons), binding them together. Once they are bound, it takes considerable energy to break them apart.
Answer:
167 kJ
Explanation:
Given parameters
Change in enthalpy = 130 kJ (decrease)
Work done = -137 kJ
Change in energy, \delta = ?
From the first law of thermodynamics:
ΔH = ΔE + PΔV,
Where, ΔH= change in enthalpy
ΔE = change in Internal energy
Substituting values into the above formula —
130 kJ = ΔE + -137 kJ
130 kJ = ΔE - 137 kJ
therefore,
ΔE = (130 + 137 ) kJ
ΔE = 167 kJ
Therefore, the change in energy of the gas mixture during the reaction is 167 kJ.
Since the value of energy change Is positive, therefore this Is endothermic reaction