Basic lab calculations (milli and micro)

Prefix Symbol Meaning deci d 10^-1 centi c 10^-2 milli m 10-3 micro µ or mc 10-6 nano n 10-9 pico p 10-12 femto f 10-15 atto a 10-18 Problem: You need to supplement the diet of a mouse with zinc. You have a solution of zinc chloride which has a concentration of 100 µg/ml. A mouse eats 5g of food per day. How much of this solution would you need to add to 100 g of laboratory animal food to supplement the mouse with 25 µg of zinc chloride per day? А) 5 ml В) 500 ml С) ml D) ml E) 0.5 ml let’s say you need 6.0 mL of 2.0 M HCl, but you only have 3.0 M HCl You could do this in different orders depending on how you like to break down these sort of questions. If we start with the food, 5g of food/day 100g total therefore we need 20 days work of ZnCl2. 20 days x 25 µg per day = 500 µg. Our stock is at 100 µg/ml therefore we need 5 ml. The other way would be to say 25 µg is ml of the stock x 20 days = 5 ml