Answer:
The mole fraction of NaOH in an aqueous solution that contain 22.9% NaOH by mass=0.882
Explanation:
We are given that
Aqueous solution that contains 22.9% NaOH by mass means
22.9 g NaOH in 100 g solution.
Mass of NaOH(WB)=22.9 g
Mass of water =100-22.9=77.1
Na=23
O=16
H=1.01
Molar mass of NaOH(MB)=23+16+1.01=40.01
Number of moles =
Using the formula
Number of moles of NaOH

Molar mass of water=16+2(1.01)=18.02g
Number of moles of water

Now, mole fraction of NaOH
=

=0.882
Hence, the mole fraction of NaOH in an aqueous solution that contain 22.9% NaOH by mass=0.882
Answer:
A. Atoms randomly crashing into each other
E. The force of one object pushing against the force of another object.
Explanation:
Forces can be classified into two categories based upon the the mode of transfer or application:
1. Contact forces
2. Non-contact forces
Contact forces are the ones which require the physical contact of the matter to get transferred and tend to create the affect. Whereas non-contact forces have the field property which transfers the affect of force from one point to another without any physical contact of the matter or the medium.
- Atoms crashing onto each other have some mass and velocity which upon collision impacts the other atoms exerts a contact force.
- The interaction between the charged particles due to their charges is always due to the electric field be it electron or proton, be it within an atom or out of an atom.
- The force between any two objects pushing or pulling each other is also possible only due to contact.
The relationship between pressure and solubility of the gas is given by Henry's law as:

where,
is the solubility of the gas.
is proportionality constant i.e. Henry's constant.
is pressure of the gas.
(given)
(given)
Substituting the values,

To convert
to
:
Molar mass of benzene,
= 

Now for converting into
:
Since, 
So,
.
Hence, the solubility of benzene in water at
in
is
.
<span>This example represents the challenge of survival of the fittest. In this situation, the trees have a distinct advantage due to their above average height. This puts them in the best position to gain the resources that they need to survive, most notably, the sun. The smaller plants, however, do not have this advantage, and lose out to the trees.</span>