Question

The formula for a sports rub cream is given in the literature as follows:

• Methyl Salicylate                          15 mL

• Menthol                                          10 g

• Eucalyptus Oil                                1 g

• Hydrophilic Ointment, qs ad        100 g

If the specific gravity of methyl salicylate is 1.18, how many grams of each ingredient (do not include units in your submitted answer) would be needed to prepare a dozen 15-g tubes of ointment? All ingredients to be added by mass, not volume.

Answer 1

To prepare, 1 dozen of 15g tubes, we need total weight of mixture equal to 180g. Given mixture constitute only 128.7g so we need to prepare 51.3g more mixture keeping the proportion of all constituents same. Here in above solution, I have used unitary method to calculate weight of all ingredients that needs to be added. After calculation, We get 7.05g of Methyl Solicylate, 3.98g Menthol, 0.39g Eucalyptus Oil and 39.8g Hydrophilic Ointment.