Respuesta :
Molarity is defined as the number of moles of solute in 1 L solution.
we have been given the mass of NaNO₃ dissolved in 250.0 mL
number of moles of NaNO₃ - 11.7 g / 85 g/mol = 0.138 mol
number of NaNO₃ moles in 250.0 mL - 0.138 mol
since molarity is the number of moles in 1 L
number of NaNO₃ moles in 1000 mL - 0.138 mol / 250.0 mL x 1000mL/L = 0.552 mol
molarity of NaNO₃ is 0.552 M
we have been given the mass of NaNO₃ dissolved in 250.0 mL
number of moles of NaNO₃ - 11.7 g / 85 g/mol = 0.138 mol
number of NaNO₃ moles in 250.0 mL - 0.138 mol
since molarity is the number of moles in 1 L
number of NaNO₃ moles in 1000 mL - 0.138 mol / 250.0 mL x 1000mL/L = 0.552 mol
molarity of NaNO₃ is 0.552 M
Answer:
[tex]0.552~M[/tex]
Explanation:
For the calculation of molarity "M" we have start with the molarity equation:
[tex]M=\frac{mol}{L}[/tex]
So, we have to calculate the moles of [tex]NaNO_3[/tex] and the L of [tex]NaNO_3[/tex].
For the calculations of moles we have to use the molar mass of [tex]NaNO_3[/tex].
Na=23 g/mol
N=14 g/mol
O= 16 g/mol
[tex]molar~mass~=~(23*1)+(14*1)+(16*3)=85~g/mol[/tex]
or
[tex]1~mol~NaNO_3=85~g~NaNO_3[/tex]
Now, we can find the moles of [tex]NaNO_3[/tex]:
[tex]11.7~g~NaNO_3*\frac{1~mol~NaNO_3}{85~g~NaNO_3} =0.138~mol~NaNO_3[/tex]
The next step would be the converstion from mL to L:
[tex]250.0~mL~*\frac{1~L}{1000~mL} =~0.25~L\\[/tex]
Finally, we have to plug both values in the molarity equation:
[tex]M=\frac{0.138~mol}{0.25~L}=~0.552~M[/tex]
