Do temperature and air pressure change in a smooth, gradual way as your balloon flies higher?

What does standard deviation reveal about data? a. the average of all the data points b. which of the data points is most reliable c. how spread out the data points are d. the percent error included in the data

How many liters of hydrogen gas will be produced at stp from the reaction of 7.179×10^23 atoms of magnesium with 54.219g of phosphoric acid (h3po4) the equation is 3mg + 2h3(> mg(po4)2+3h2

The number of neutrons is equal to the atomic number minus the atomic mass. a. true b. false