Molarity is defined as the ratio of number of moles to the volume of solution in litres.
The mathematical expression is given as:
Here, molarity is equal to 1.43 M and volume is equal to 785 mL.
Convert mL into L
As, 1 mL = 0.001 L
Thus, volume = 
= 0.785 L
Rearrange the formula of molarity in terms of number of moles:
n = 
= 1.12255 mole
Now, Number of moles = 
Molar mass of potassium hydroxide = 56.10 g/mol
1.12255 mole = 
mass in g = 
= 62.97 g
Hence, mass of 
= 62.97 g
Answer:
P' = 41.4 mmHg → Vapor pressure of solution
Explanation:
ΔP = P° . Xm
ΔP = Vapor pressure of pure solvent (P°) - Vapor pressure of solution (P')
Xm = Mole fraction for solute (Moles of solvent /Total moles)
Firstly we determine the mole fraction of solute.
Moles of solute → Mass . 1 mol / molar mass
20.2 g . 1 mol / 342 g = 0.0590 mol
Moles of solvent → Mass . 1mol / molar mass
60.5 g . 1 mol/ 18 g = 3.36 mol
Total moles = 3.36 mol + 0.0590 mol = 3.419 moles
Xm = 0.0590 mol / 3.419 moles → 0.0172
Let's replace the data in the formula
42.2 mmHg - P' = 42.2 mmHg . 0.0172
P' = - (42.2 mmHg . 0.0172 - 42.2 mmHg)
P' = 41.4 mmHg
The term that describes when a solvent is holding as much solute in solution as it is able for a given temperature is called supersaturated solution. A little disturbance to this solution some of the solute will crystallize or precipitate out since this solution is not stable.
Answer:
4L
Explanation:
To obtain the volume of O2 at stp, first, we need to determine the number of mole of O2.
From the question given above,
Mass of O2 = 5.72g
Molar Mass of O2 = 32g/mol
Number of mole =Mass/Molar Mass
Number of mole of O2 = 5.72/32
Number of mole of O2 = 0.179 mole
Now, we can calculate the volume of O2 at stp as follow:
1 mole of a gas occupy 22.4L at stp.
Therefore, 0.179 mole of O2 will occupy = 0.179 x 22.4 = 4L
Therefore, the volume occupied by the sample of O2 is 4L
I. Lowering the temperature would decrease the rate of the reaction.
