Answer:
Mole fraction of Nacl is 0.173
Explanation:
we know that

where,
P
sol - the vapor pressure of the solution
χ solvent - the mole fraction of the solvent
P
∘
solvent - the vapor pressure of the pure solvent
This means that in order to be able to calculate the mole fraction of sodium chloride, you need to know what the vapor pressure of pure water is at
25
°
C You can use an online calculator to find that the vapor pressure of pure water at 25 C is equal to about 23.8 torr
.

=0.827
Also we know that

This means that the mole fraction of sodium chloride is
χ_{Nacl}= 1-Χ_{water}
= 1-0.827 =0.173
Answer:
3 element i.e carbon (C), hydrogen (H) and oxygen.
Explanation:
The following data were obtained from the question:
Subtance >>>>>>>> Chemical Formula
Glucose >>>>>>>>> C₆H₁₂O₆
Methane >>>>>>>> CH₄
Ethanol >>>>>>>>> C₂H₅OH
Hydrogen peroxide >> H₂O₂
From the above table, we can see that ethanol (C₂H₅OH) contains carbon (C), hydrogen (H) and oxygen
Therefore, the total number of elements present in ethanol, C₂H₅OH is 3.
Answer:
Q=mcΔT
Explanation:
The formula for expressing the amount of heat transferred between energy stores is given by the equation. The specific heat capacity of water is 4180 J/kgoC (Joules per kilogram per degree), this means it takes 4180 J of heat energy to raise the temperature of 1 kg of water by 1oC.