Answer: mole fraction of methanol = 0.590
mole fraction of ethanol = 0.410
Explanation:
We are given:
Equal masses of methanol 
and ethanol 
are mixed.
let the mass be x g.
Calculating the moles of methanol in the solution, by using the equation:
Calculating the moles of ethanol in the solution, by using the equation:
To calculate the mole fraction of methanol, we use the equation:
To calculate the mole fraction of ethanol, we use the equation:
Thus mole fraction of methanol is 0.590 and mole fraction of ethanol 0.410 in three significant figures.
Explanation:
The species with a positive charge over it, which means lack of electrons are called cations. Whereas the species with negative over it, meaning it has an excess of electrons with it are called anions.
From the list given the cations are
H+, Ba2+, Hg2+, Li+, Ca2+ and Fe2+
Whereas anions from the list are
O-2, Br-5, F-, S-2.
A Combination of cation and anions make an ionic compound in which cation is written first and then anion.
Answer: 20.7 kJ
Explanation:
According to first law of thermodynamics:
=Change in internal energy
q = heat absorbed or released
w = work done or by the system
w = work done on the system=
{Work is done on the system is positive as the final volume is lesser than initial volume}
w = 4.51 kcal = 
(1kcal = 4.184kJ)
q = +1.79 kJ {Heat absorbed by the system is positive}
Thus for a system that receives 1.79 kJ of heat from surroundings and has 4.51 kcal of work done on it at the same time is 20.7 kJ
Answer: False
Explanation: The nucleus of an atom only contains the protons and neutrons.
The electrons are not found in the nucleus,
they are orbiting the nucleus in different shells.
