Ethane (C2H6) burns with oxygen to produce carbon dioxide and water. A sample of ethane was burned completely and the water that formed had a mass of 1.61g. How much ethane, in moles and in grams, was in the sample?

Answer 1

Write the equation and balance it.
2C2H6 + 7O2 ==> 4CO2 + 6H2O

Here is a stoichiometry problem I've posted. Just follow the steps in the example.
http://www.jiskha.com/science/chemistry/stoichiometry.html