Question

Potassium cyanide is a toxic substance, and the median lethal dose depends on the mass of the person or animal that ingests it. The median lethal dose of KCN for a person weighing 215 lb (97.5 kg ) is 8.84×10−3 mol .
What volume of a 0.0250 M KCN solution contains 8.84×10−3 mol of KCN?

Express the volume to three significant figures and include the appropriate units.

Answer 1

Answer:

0.354L

Explanation:

Given parameters:

Molarity of KCN  = 0.025M

Number of moles  = 8.84 x 10⁻³mol

Unknown:

Volume of KCN  = ?

Solution:

The molarity of a substance is expressed as;

       Molarity  = $\frac{number of moles }{volume }$  

 Volume of KCN   = $\frac{number of moles }{molarity}$

Now insert the parameters and solve;

  Volume of KCN  = $\frac{0.00884}{0.025}$   = 0.354L