How many grams of salicylic acid should be added to 75 g of a polyethylene glycol ointment to prepare an ointment containing 6% w/w of salicylic acid?
The answer is 4.79 but I don't know how to get the answer. Please help. thanks!
How many grams of salicylic should be added to 75 g of a polyethylene ointment to prepare an ointment containing 6% w/w of salicylic?
2020-11-07 4:55 pm
回答 (1)
2020-11-07 5:20 pm
✔ 最佳答案
x / (x + 75) = 6/100100 * x = 6 * (x + 75)
100x = 6x + 450
94x = 450
47x = 225
x = 225/47
x = 4.7872340425531914893617021276596
Rounded to the nearest hundredth is 4.79
However, we really should use 2 significant figures, which means the real answer is 4.8 grams.
收錄日期: 2021-04-24 08:11:35
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