What is the density of 45.6g rock that occupies 24ml

The atomic number, or number, is the described as the number of in the nucleus of an chemical element.

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

What produces wave a)sound b) heats c)transfer of energy d)vibrations