Answer:
Composition of the mixture:
%
%
Composition of the vapor mixture:
%
%
Explanation:
If the ideal solution model is assumed, and the vapor phase is modeled as an ideal gas, the vapor pressure of a binary mixture with
and
molar fractions can be calculated as:

Where
and
are the vapor pressures of the pure compounds. A substance boils when its vapor pressure is equal to the pressure under it is; so it boils when
. When the pressure is 0.60 atm, the vapor pressure has to be the same if the mixture is boiling, so:

With the same assumptions, the vapor mixture may obey to the equation:
, where P is the total pressure and y is the fraction in the vapor phase, so:
%
The fractions of B can be calculated according to the fact that the sum of the molar fractions is equal to 1.
Helium
Remember: electron filling of atomic shell ...
The element which have electron in the lowest quantum shell will have the smallest atomic radius\
He:1s1 (Helium)
H:1s2 (hydrogen)
Answer:
1.4 g H₂O
Explanation:
In a reaction, the reactants are usually not present in exact <em>stoichiometric amounts</em>, that is, <em>in the proportions indicated by the balanced equation</em>. Frequently a large excess of one reactant is supplied to ensure that the more expensive reactant is completely converted to the desired product. Consequently, some reactant will be left over at the end of the reaction. T<em>he reactant used up first in a reaction</em> is called the <em>limiting reagent</em>, because <u>the maximum amount of product formed depends on how much of this reactant was originally present</u>. When this reactant is used up, no more product can be formed.