Question 1

Can I use percentages in this formula?

Accepted Answer

Yes, as long as both concentrations are the same kind of percentage (both % w/v or both % v/v).

Question 2

How do I dilute 1:100 with a small final volume?

Accepted Answer

For 10 mL, use 0.1 mL of stock and 9.9 mL of diluent, or do two 1:10 steps for better accuracy.

Question 3

What is the difference between dilution factor and dilution ratio?

Accepted Answer

The factor is total volume ÷ stock volume (20 here); a ratio is often written as stock : diluent (1 : 19). Check which convention a protocol uses.

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