What do we call the mass of an element in a compond compared to the entire mass of the compound?

In any energy conversion, some of the energy is lost to the environment as question 5 options: electrical energy potential energy sound energy thermal energy

What is the empirical formula of c6h18o3? ch3o c2h5o c2h6o c2h5o5

1) which of the following is the best example of a physical change? a) sugar dissolving in tea b) firefly glowing 2) in the combustion of ethane, what is/are the reactants? c2h6 + o2 ==> co2 + h2o a) c2h6 and o2 b) co2 and c2h6