that seems very false but I believe its the second one
Answer: 0.004 moles
Explanation:
Amount of substance= mass/ molar mass
Mass= 250mg or 0.25g
Molar mass= 58.44gmol-1
Amount= 0.25/58.44
= 0.004 moles
To answer this question, you need to know <span>Graham's Law of Effusion/Diffusion formula. In this formula, the rate of diffusion/effusion would be influenced by the mass. As the molecule has bigger mass, the rate should be slower because it will be harder to pass the membrane. The calculation should be:</span>
<span>Rate 1 / Rate 2 = √[M2/M1]
</span>4.11/1= √[M2/2]
M2=33.78 g/mol
Answer:
<h2>mass = 29.25 g</h2>
Explanation:
The denisty of a substance can be found by using the formula

Making mass the subject we have
<h3>mass = Density × volume</h3>
From the question
Density = 2.34 g/mL
volume = 12.50 mL
Substitute the values into the above formula and solve for the mass
That's
mass = 2.34 × 12.50
We have the final answer as
<h3>mass = 29.25 g</h3>
Hope this helps you