Answer:
D. 20.6g
Explanation:
Molarity is defined as ratio between moles of solute (sodium bromide, NaBr) per liter of water.
As density of water is 1g/mL; volume of 400.0g of water is 400.0mL = 0.4000L.
That means 0.400L of 0.500M solution contains:
0.400L × (0.500mol / 1L) = <em>0.200moles of sodium bromide</em>.
In mass (NaBr = 102.9g/mol):
0.200mol NaBr × (102.9g/mol) = 20.6g of NaBr
Right answer is:
<em>D. 20.6g</em>
