Duncan takes a break from studying and goes to the gym to swim laps. If swimming burns 7.85×105 cal per hour, how many kilojoules does swimming burn in that same amount of time? In other words, convert 7.85×105 cal to kilojoules. Express your answer numerically in kilojoules.

Why is it that 85.48 rounded to two significant figures is 85 and not 86?

The element chlorine has two stable isotopes, chlorine-35 with a mass of 34.97 amu and chlorine-37 with a mass of 36.95 amu. from the atomic weight of cl = 35.45 one can conclude that:

Fill in the blanks for the following statements: the rms speed of the molecules in a sample of h2 gas at 300 k will be times larger than the rms speed of o2 molecules at the same temperature, and the ratio µrms (h2) / µrms (o2) with increasing temperature. a not enough information is given to answer this question b sixteen, will not change c four, will not change d four, will increase e sixteen, will decrease