Each hydrogen atom contains protons. each oxygen atom contains neutrons. electron(s) is (are) needed to complete hydrogen's outer shell. electron pair(s) is (are) being shared between the hydrogen atoms and the bonded oxygen. bond(s) exist(s) between the hydrogen and the oxygen atom. there are electrons are in oxygen's outer orbit. the orbit of oxygen has two electrons. its a water molicule i need the numer for

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

If a gas has an initial pressure of 101kpa and a volume of 10l, then it expands to a volume of 20l, what is the new pressure?

Read "who built the pyramids? ”. leave this link open while you answer the questions throughout the assignment. give at least two reasons why some people claim the pyramids of giza were constructed by aliens.