Calculate concentration of caffeine

210mg/L of caffeine stock is prepared in a 100ml volumetric flask. Then 4 standards is prepared with the stock. One with 1ml stock, 2ml stock, 4ml stock and 6ml stock. All is then diluted in a 50ml volumetric flask. What is the concentration in mg/L of all 4 standard ?

Question

Calculate concentration of caffeine 

210mg/L of caffeine stock is prepared in a 100ml volumetric flask. Then 4 standards is prepared with the stock. One with 1ml stock, 2ml stock, 4ml stock and 6ml stock. All is then diluted in a 50ml volumetric flask. What is the concentration in mg/L of all 4 standard ?

aaronq · Answer

$\underbrace{C_1V_1}_{stock}=\underbrace{C_2V_2}_{dilution}$

C= concentration; V=volume