This may be in wrong section but this is for a biology exam.
How would I go about answering this:
When provided with 2.0% Sodium chloride solution, how would you make 10cm3 of the following concentrations of Sodium chloride:
0.0%
0.3%
0.7%
0.9%
1.5%
How would I go about answering this:
When provided with 2.0% Sodium chloride solution, how would you make 10cm3 of the following concentrations of Sodium chloride:
0.0%
0.3%
0.7%
0.9%
1.5%
-
Approach the answer this way-
10 cm^3 of 0.9% NaCl contains0.09 g NaCl (10 x .009 = 0.09)
You want X cm^3 of 2% solution containing 0.09 g NaCl
X xm^3 of 2.0% NaCl contains 0.09 g NaCl (X * .02 = 0.09; X = 0.09/0.02 = 4.5)
4.5 cm^3 of 2.0% NaCl diluted to 10^3 with water yields 10 cm^3 of 0.9% NaCl
0 cm^3 diluted to 10 cm^3 --> 0.0%
1.5 cm^3 diluted to 10 cm^3 --> 0.3%
3.5 cm^3 diluted to 10 cm^3 --> 0.7%
4.5 cm^3 diluted to 10 cm^3 --> 0.9%
7.5 cm^3 diluted to 10 cm^3 --> 1.5%
10 cm^3 of 0.9% NaCl contains0.09 g NaCl (10 x .009 = 0.09)
You want X cm^3 of 2% solution containing 0.09 g NaCl
X xm^3 of 2.0% NaCl contains 0.09 g NaCl (X * .02 = 0.09; X = 0.09/0.02 = 4.5)
4.5 cm^3 of 2.0% NaCl diluted to 10^3 with water yields 10 cm^3 of 0.9% NaCl
0 cm^3 diluted to 10 cm^3 --> 0.0%
1.5 cm^3 diluted to 10 cm^3 --> 0.3%
3.5 cm^3 diluted to 10 cm^3 --> 0.7%
4.5 cm^3 diluted to 10 cm^3 --> 0.9%
7.5 cm^3 diluted to 10 cm^3 --> 1.5%
-
http://answers.yahoo.com/question/index?…