Hi another chemistry question sorry!?

Question

Ethers (general formula, R-O-R') have many important uses. Until recently, methyl tert-butyl ether (MTBE, see structure below) was used as an octane booster and fuel additive for gasoline. It increases the oxygen content of the fuel, which reduces CO emissions during winter months. MTBE is synthesized by reacting 2-methylpropene with methanol.
If the government required that auto fuel mixtures contain 2.8% by mass oxygen to reduce CO emissions, how many grams of MTBE would have to be added to each 100. g gasoline?

Answer 1

MTBE is CH3OC(CH3)3, so its MW is 88, of which 16 is O, or 18.2% by weight.

So, to get the 2.8% by mass oxygen, you would use:

0.028 = 0.182 x / (100 + x)
2.8 + 0.028 x = 0.182 x
2.8 = 0.154 x
x = 18.2

18.2 g of MTBE must be added to each 100 g of gasoline, giving a total of 118.2 g, which would be 2.8% by weight oxygen.

MTBE's use has been reduced if not eliminated however as it is somewhat water-soluble and has found a way to get into the water supply.

Answer 2

Mtbe Structure