Answer:
1.55 mol
Step-by-step explanation:
We can use the <em>Ideal Gas Law</em> to solve this problem.
pV = nRT Divide both sides by RT
n = (pV)/(RT)
Data:
p = 1.40 atm
V = 27.5 L
R = 0.082 06 L·atm·K⁻¹mol⁻¹
T = 302 K
Calculations:
n = (1.40 × 27.5)/(0.082 06 × 302)
= 1.55 mol
The volume of one mole of gas is 22.4 liters at 0 °C and 760 Torr. The volume of the given condition can be calculated using:
(PV)/T = constant
(P₁V₁)/T₁ = (P₂V₂)/T₂
(760 * 22.4)/273 = (792 * V₂) / 321.7
V₂ = 25.3 Liters
The Mr of He = 4
The Mr of Ne = 20
Density of He = 4/25.3 = 0.1581 g/L
Density of Ne = 20/25.3 = 0.7905 g/L
Let x be the fraction of Ne
1 - x is the fraction of He
avg density = sum[(mole fraction * Mr)/V]
0.6048 = (20x + 4(1 - x))/25.3
x = 0.70
Answer:
0.311 mmol/L
Explanation:
109 μmol = 109*10^(-6) mol
109*10^(-6) mol = 109*10^(-6) mol*(10^3 mmol/1mol) = 109*10^(-3) mmol =
=0.109 mmol
350 mL = 0.350 L
0.109 mmol/0.350 L = 0.311 mmol/L
Unfortunately the data provided doesn't include the DENSITY of the ammonium chloride solution and molarity is defined as moles per volume. So without the density, the calculation of the molarity is impossible. But fortunately, there are tables available that do provide the required density and for a 20% solution by weight, the density of the solution is 1.057 g/ml.
So 1 liter of solution will mass 1057 grams and the mass of ammonium chloride will be 0.2 * 1057 g = 211.4 g. The number of moles will then be 211.4 g / 53.5 g/mol = 3.951401869 mol. Rounding to 3 significant digits gives a molarity of 3.95.
Now assuming that your teacher wants you to assume that the solution masses 1.00 g/ml, then the mass of ammonium chloride will only be 200g, and that is only (200/53.5) = 3.74 moles.
So in conclusion, the expected answer is 3.74 M, although the correct answer using missing information is 3.95 M.
Answer:1 grams Magnesium Hydroxide is equal to 0.017146870490373 mole.
Explanation:The molecular formula for Magnesium Hydroxide is Mg(OH)2. The SI base unit for amount of substance is the mole.
