Answer:
Explanation:
Excess fertilizers, herbicides and insecticides from agricultural lands and residential areas.
Oil, grease and toxic chemicals from urban runoff and energy production.
Sediment from improperly managed construction sites, crop and forest lands, and eroding streambanks.
Impure substance, because pure would be dirt from the earth
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>