Read the sentence from the section “The Law Of Conservation Of Mass."

In a physical change, a substance's physical properties may change, but its chemical makeup does not.

Which of the following words, if it replaced the word "properties" in the sentence above, would CHANGE the meaning of the sentence?

Write the chemical formula for a compound that is made of an element from group 1 and an element from group 17

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 .

What is the energy in joules of a mole of photons associated with visible light of wavelength 486 nm?