Answer:
8.3028894e-22
Explanation:
5x10^2 atoms/1 x 1 mol/6.022x10^23
Answer:
Evaporation is the method of separating a solid (solute) from a homogeneous solution.
in this method, the solution is heated until the solvent gets evaporated in the form of vapor and the solute is left behind as residue.
To solve the problem, we assume the sample to be ideal. Then, we use the ideal gas equation which is expressed as PV = nRT. From the first condition of the nitrogen gas sample, we calculate the number of moles.
n = PV / RT
n = (98.7x 10^3 Pa x 0.01 m^3) / (8.314 Pa m^3/ mol K) x 298.15 K
n = 0.40 mol N2
At the second condition, the number of moles stays the same however pressure and temperature was changed. So, the new volume is calculated as follows:
V = nRT / P
V = 0.40 x 8.314 x 293.15 / 102.7 x 10^3
V = 9.49 x 10^-3 m^3 or 9.49 L
Answer: I & III
Explanation: Solutes are the substances which are minimum in quantity and which is required to dissolve in the solvent (which is larger in quantity) in order to make a solution.
In the asked question, it is given that the water is the solvent and from the given solutes we have to pick which would make an aqueous solution with the highest concentration of solute possible.
Thus the most appropriate answers could be the Ammonia and hexanol which can make the highest possible concentration of solute as ammonia is the gas which is highly soluble in water and hexanol is an alcohol which has an affinity for water. Thus the correct option is I & III
Answer:
The concentration of this solution in units of pounds per gallon is 
Explanation:
Units of measurement are established models for measuring different quantities. The conversion of units is the transformation of a quantity, expressed in a certain unit of measure, into an equivalent one, which may or may not be of the same system of units.
In this case, the conversion of units is carried out knowing that 1 μg are equal to 2.205*10⁻⁹ Lb and 1 mL equals 0.00022 Gallons. So

If 1 μg equals 2.205*10⁻⁹ lb, 2.77 μg how many lb equals?

lb=6.10785*10⁻⁹
So, 2.77 μg= 6.10785*10⁻⁹ lb
Then:

You get:

<u><em>The concentration of this solution in units of pounds per gallon is </em></u>
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