Ahydrocarbon is a compound that contains mostly carbon and hydrogen. calculate the percent composition (by mass) of the following hydrocarbon: c 7 h 16 . enter the percentages of carbon and hydrogen numerically to four significant figures, separated by commas.

Asample of the male sex hormone testosterone, c19h28o2, contains 3.88×10^21 atoms of hydrogen.(a) how many atoms of carbon does it contain? (b) how many molecules of testosterone does it contain? (c) how many moles of testosterone does it contain? (d) what is the mass of this sample in grams?

Imagine that you’re getting ready to move to a new city. when people move, they are influenced by push factors and pull factors, and you have many reasons for your move. which of the following factors is an example of a pull factor? a. wanting to move because you’ve found a great new school somewhere new b. needing to move because there are not enough resources in your old hometown c. being forced to move because your old home is gone d. having to move because there are no jobs in your current hometown

As air becomes more dense, (select all that apply) o. air weighs less o. gas molecules are closer together o. air is colder o. air weighs more o. gas molecules are further apart o. air is hotter