Answer:
0.5 M
Explanation:
First we have to start with the molarity equation:
[tex]M=\frac{mol}{L}[/tex]
We need to know the amount of moles and the litters.
If we have 100 mL we can convert this value to “L”, so:
[tex]100~mL\frac{1~L}{1000~mL}[/tex]
[tex]0.1~ L[/tex]
Now we can continue with the moles, for this we have to know the formula of sodium sulfate [tex]Na_2SO_4[/tex], with this formula we can calculate the molar mass if we know the atomic mass of each atom on the formula (Na: 23 g/mol, S: 32 g/mol, O: 16 g/mol). We have to multiply each atomic mass by the amount of atoms in the formula, so:
[tex]molar~ mass~=~ (23*2)+(32*1)+(16*4)= ~ 142~ g/mol[/tex]
In other words:
[tex]1~mol~ Na_2SO_4=~142~g~ of~Na_2SO_4[/tex]
Now we can calculate the moles:
[tex]7.1~g~ of~Na_2SO_4\frac{1~mol~ Na_2SO_4}{142~g~ of~Na_2SO_4} [/tex]
[tex]0.05~mol~ Na_2SO_4 [/tex]
Finally, we can calculate the molarity:
[tex]M=\frac{0.05~mol~ Na_2SO_4 }{0.1~ L}[/tex]
[tex]M=0.5[/tex]
I hope it helps!
Answer:
0.50M of solution
Explanation:
Molarity is defined as the ratio between moles of solute (In this case, sodium sulfate, Na₂SO₄) per liter of solution.
Moles of 7.1g of Na₂SO₄ (Molar mass: 142g/mol) are:
7.1g Na₂SO₄ × (1mol / 142g) = 0.05 moles of Na₂SO₄.
In 100mL = 0.100L:
0.05 moles Na₂SO₄ / 0.100L = 0.50M of solution
