If someone takes a breath and the lungs expand from 4.5 L to 5.6 L in volume and the initial pressure inside the lungs is 756 mmHG what is the pressure inside the lungs before any additional air is pulled in

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

Chemistry worksheet - i am not sure what they are asking for exactly?

Draw the lewis dot structure for each of the following polyatomic ions