What happens when a chlorine atoms gains an electron? select one: a. the ion has a -1 charge b. a chloride ion is formed c. the ion becomes an anion d. all of the answer choices

To calculate percent by mass, use the equation below: calculate the percent by mass of each element. %n = % %h = % %o = %

Nitric acid can be formed in two steps from the atmospheric gases nitrogen and oxygen, plus hydrogen prepared by reforming natural gas. in the first step, nitrogen and hydrogen react to form ammonia: (g) (g) (g) in the second step, ammonia and oxygen react to form nitric acid and water: (g) (g) (g) (g) calculate the net change in enthalpy for the formation of one mole of nitric acid from nitrogen, hydrogen and oxygen from these reactions. round your answer to the nearest .

Which radioisotope is used to date fossils? a. oxygen-16 b. carbon-14 c. uranium-238 d. carbon-12