Calculate the root mean square velocity of the CH4 molecules in a sample of CH4 gas at 273 K and at 546 K.

Which of the following would be an accurate picture of the earth during the summer time of the northern hemisphere?

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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