Why does the nitrogen concentration decrease after hydrogen is added? n2(g)+3h2(g)⇌2nh3(g) why does the nitrogen concentration decrease after hydrogen is added?

The chemical reaction of a reversible reaction is actually governed by Le Chatelier’s principle. It states that when more reactants are introduced into the system, the reaction will proceed forward to create more products. So since Hydrogen is a reactant and Nitrogen is also reactant so adding more Hydrogen makes more products hence reducing the Nitrogen concentration.

they begin to vibrate harder causing the material that was solid to turn into a liquid i.e gallium or ice

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance