Serial dilution: practice problems Work out the concentration in each tube, the transfer volume, and the diluent per tube. Every answer here is computed by the same tested calculator the rest of the site uses, so a solution can never drift away from the maths.
Problem 1 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 1 M Fold factor: 10 Number of tubes: 6 Volume per tube: 1 mL Show the answer and the working 6 tubes at a 10× dilution, from 1 M down to 1 × 10⁻⁶ M.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 1 mL / 10 = 0.1 mL Diluent per tube: V₂ − V_t = 0.9 mL Series: 6 step(s) of 10× from 1 M Open this in the calculator to change the numbers.
Problem 2 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 500 µM Fold factor: 2 Number of tubes: 7 Volume per tube: 750 µL Show the answer and the working 7 tubes at a 2× dilution, from 500 µM down to 3.906 µM.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 750 µL / 2 = 375 µL Diluent per tube: V₂ − V_t = 375 µL Series: 7 step(s) of 2× from 500 µM Open this in the calculator to change the numbers.
Problem 3 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 2 M Fold factor: 10 Number of tubes: 4 Volume per tube: 1 mL Show the answer and the working 4 tubes at a 10× dilution, from 2 M down to 0.0002 M.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 1 mL / 10 = 0.1 mL Diluent per tube: V₂ − V_t = 0.9 mL Series: 4 step(s) of 10× from 2 M Open this in the calculator to change the numbers.
Problem 4 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 500 µM Fold factor: 2 Number of tubes: 5 Volume per tube: 300 µL Show the answer and the working 5 tubes at a 2× dilution, from 500 µM down to 15.63 µM.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 300 µL / 2 = 150 µL Diluent per tube: V₂ − V_t = 150 µL Series: 5 step(s) of 2× from 500 µM Open this in the calculator to change the numbers.
Problem 5 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 1 M Fold factor: 10 Number of tubes: 4 Volume per tube: 4 mL Show the answer and the working 4 tubes at a 10× dilution, from 1 M down to 0.0001 M.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 4 mL / 10 = 0.4 mL Diluent per tube: V₂ − V_t = 3.6 mL Series: 4 step(s) of 10× from 1 M Open this in the calculator to change the numbers.
Problem 6 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 500 µM Fold factor: 2 Number of tubes: 6.5 Volume per tube: 200 µL Show the answer and the working 7 tubes at a 2× dilution, from 500 µM down to 3.906 µM.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 200 µL / 2 = 100 µL Diluent per tube: V₂ − V_t = 100 µL Series: 7 step(s) of 2× from 500 µM Open this in the calculator to change the numbers.
Problem 7 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 1 M Fold factor: 10 Number of tubes: 3.5 Volume per tube: 4 mL Show the answer and the working 4 tubes at a 10× dilution, from 1 M down to 0.0001 M.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 4 mL / 10 = 0.4 mL Diluent per tube: V₂ − V_t = 3.6 mL Series: 4 step(s) of 10× from 1 M Open this in the calculator to change the numbers.
Problem 8 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 750 µM Fold factor: 2 Number of tubes: 7 Volume per tube: 200 µL Show the answer and the working 7 tubes at a 2× dilution, from 750 µM down to 5.859 µM.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 200 µL / 2 = 100 µL Diluent per tube: V₂ − V_t = 100 µL Series: 7 step(s) of 2× from 750 µM Open this in the calculator to change the numbers.
Problem 9 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 1 M Fold factor: 10 Number of tubes: 3 Volume per tube: 1 mL Show the answer and the working 3 tubes at a 10× dilution, from 1 M down to 0.001 M.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 1 mL / 10 = 0.1 mL Diluent per tube: V₂ − V_t = 0.9 mL Series: 3 step(s) of 10× from 1 M Open this in the calculator to change the numbers.
Problem 10 Serial dilution Work out the concentration in each tube, the transfer volume, and the diluent per tube.
Stock concentration: 250 µM Fold factor: 2 Number of tubes: 6 Volume per tube: 200 µL Show the answer and the working 6 tubes at a 2× dilution, from 250 µM down to 3.906 µM.
Per-tube concentration: Cₙ = C_stock / fⁿ Transfer volume: V_t = V₂ / f = 200 µL / 2 = 100 µL Diluent per tube: V₂ − V_t = 100 µL Series: 6 step(s) of 2× from 250 µM Open this in the calculator to change the numbers.
More dilutions practice
Same topic, different calculation C₁V₁ = C₂V₂, exactly how much stock and diluent to mix.
Turn a bottle label (%w/w + density) into a safe dilution protocol.
Stuck on one of them? Open it in the calculator and it shows the same working step by step, with the units checked and the hazards flagged. Free, no account, and it keeps working offline once the page has loaded.
Open the Serial dilution calculator