Actually it’s A not B. If you got this question off of USA Test Prep, the answer is A
D. Rutherford's gold foil experiment
Answer:
n₂ = 0.2 mol
Explanation:
Given data:
Volume of 1st balloon = 2.5 L
Moles of He in 1st balloon = 0.100 mol
Volume of second balloon = 5.0 L
Moles in second balloon = ?
Solution:
According to the Avogadro law,
Number of moles of gas is directly proportional to the volume of gas at constant temperature and pressure.
Mathematical expression:
V₁/n₁ = V₂/n₂
V₁ = Volume of 1st balloon
n₁ = Moles of He in 1st balloon
V₂ = Volume of second balloon
n₂ = Moles in second balloon
Now we will put the values.
2.5 L / 0.100 mol = 5 L /n₂
n₂ = 5 L× 0.100 mol /2.5 L
n₂ = 0.5 mol /2.5
n₂ = 0.2 mol
Answer:
0.0894 M
Explanation:
So you first want to change the grams into moles (since molarity is moles solute per Liter solution).
The molar mass of NaNO3 is 84.995 g/mol, so we divide 0.38g of NaNO3 by 84.995 g/mol to get approximately 0.004471 mol NaNO3.
Now, all you have to do is to divide by the total Liters of water (your solution).
Since the volume is expressed in mL, you just need to divide by 1000 (1 L = 1000mL) to get 0.050 L solution.
Therefore, to get molarity, you divide 0.004471 mol by 0.050 L to get your answer of 0.0894 M.
Answer:
Due to Presence of free electrons.
