Vitamin A has a molar mass of 286.4 g/mol and has a general molecular formula of CxHyE, where is an unknown element. If vitamin A is 83.96% C and 10.56 % H by mass, what is the molecular formula of vitamin A?

How does the viscosity of magma change as magma cools?

Oil rich countries in the middle east cover about 4% of earths total land area but prossess about 48% of the worlds known oil reserves what is the main reason for high concentration of reserves in this part of the world

A5 mole sample of liquid acetone is converted to a gas at 75.0°c. if 628 j are required to raise the temperature of the liquid to the boiling point, 15.600 kj are required to evaporate the liquid, and 712 j are required to raise the final temperature to 75.0°c, what is the total energy required for the conversion?