Answer:
25 mL,50 mL, 20 mL
Explanation:
Molarity = numbers of mole / volume in liters
Glucose
stock solutions concentration = 1M
concentration needed = 0.05 M
volume of the preparation = 500ml = 500 / 1000 = 0.5l
number of moles of glucose in the solution = Molarity × molar mass = 0.05 × 0.5 L = 0.025 moles
volume of the stock needed = number of moles / molarity of the stock solution = 0.025 moles / 1 M = 0.025L = 25 mL
Asparagine
Molarity of the stock solution = 100mM = 0.1 M
Molarity needed = 10mM = 0.01 M
volume of the prepared solution = 0.5 L
number of moles in the prepared solution = 0.01 M × 0.5 L = 0.005 moles
volume of the stock solution needed = number of moles of the prepared solution / Molarity of the stock = 0.005 / 0.1 = 0.05L = 50 mL
NaH₂PO₄
Molarity of the stock solution = 50 mM = 0.05 M
Molarity of the needed = 2 mM = 0.002 M
Volume of the prepared solution = 0.5 L
number of moles in the prepared solution = 0.002 M × 0.5 L = 0.002 × 0.5 L = 0.001 moles
volume of the stock needed = 0.001 moles / 0.05 M = 0.02 L = 20 mL
