What is the molarity of a solution in which 10.0g of AgNO_3 is dissolved in 500. mL of solution?
1 Answer
Explanation:
Molarity is simply a measure of the concentration of a solution in terms of how many moles of solute are present per liter of solution.
color(blue)(|bar(ul("molarity" = "moles of solute"/"liters of solution"))|)
This means that in order to find a solution's molarity you must know two things
- the number of moles of solute present
- the volume of the solution
In order to find the number of moles of silver nitrate,
10.0 color(red)(cancel(color(black)("g"))) * "1 mole AgNO"_3/(169.87color(red)(cancel(color(black)("g")))) = "0.05887 moles AgNO"_3
Now, do not forget that molarity is expressed per liter of solution. This means that you're going to have to convert the volume from milliliters to liters by using the conversion factor
"1 L" = 10^3"mL"
Plug in your values to get
color(blue)( |bar(ul(c = n_"solute"/V_"solution"))|)
c = "0.05887 moles"/(500. * 10^(-3)"L") = color(green)(|bar(ul("0.118 M"))|)
The answer is rounded to three sig figs.
