Question
To make 10 mL of 25 mM sodium standard, what volume of 1 M NaCl stock should be used?
250 mL
2.5 mL
0.25 mL
0.5 mL
None of these
400 mL
250 mL
2.5 mL
0.25 mL
0.5 mL
None of these
400 mL
Answers
bobpursley
Hmmm. mM? is that milliMolar?
If so, you are diluting it 1/.025 times, or 40 times, so you need 1 part stock, 39 parts water.
1/40 th of 10 ml is 10ml/40= .25ml stock
check my thinking
If so, you are diluting it 1/.025 times, or 40 times, so you need 1 part stock, 39 parts water.
1/40 th of 10 ml is 10ml/40= .25ml stock
check my thinking