How Many Grams of Solute Are Needed for Specific Solution Concentrations?

[DB]

What mass of solute do you need to make 50 ml of a 20 g/L solution?

$$\frac{20_g}{1000_{ml}}=\frac{x_{g}}{50_{ml}}$$

20 g/L = 1 g/50ml

Answer: 1 g

How many grams of solute are there in 300 g of .50% NaCl solution

$$.50%=\frac{x_g}{300_{ml}} * 100$$
$$.005%=\frac{x_g}{300_{ml}}$$
x=1.5 grams

How'd I do?

Thanks

 

[DB]

lol 1 more

How many grams of solute are needed to prepare 250 ml of a 10 mol/L HCl solution

1 mol of HCl=36 grams (Cl=35 + H=1)

$$\frac{10_{mol}}{1000_{ml}}=\frac{x_{mol}}{250_{ml}}$$

2.5 mol x 36 = 90 grams

?

 

[dextercioby]

The second is okay.I wish you had put the zero before the dot,as it's highly misleading...

The last is okay.

Daniel.

 

[DB]

thanks, sorry bout the zero