For the gas phase reaction n2 + 3 h2 < => 2 nh3 δhº = -92 kj for the forward reaction. in order to increase the amount of h2 present, the reaction should be run

In order to increase the amount of H₂ present, the reaction should be run at high temperatures and low pressures.

Explanation:

Let's consider the following gas phase reaction.

N₂(g) + 3 H₂(g) ⇄ 2 NH₃(g)    ΔHº = -92 kJ

To predict how the reaction will proceed when we introduce modifications we need to consider Le Chatelier's Principle: If a system at equilibrium suffers a perturbation, it will react to counteract such perturbation.

ΔHº < 0 means that the reaction is exothermic. If we increase the temperature, the system will decrease it favoring the reverse reaction to absorb heat. As a side-effect the amount of H₂ increases.

If we decrease the pressure, the system will increase it by favoring the reverse reaction so that there are more gaseous moles and more pressure. As a side-effect the amount of H₂ increases.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

the answer is the first option

explanation:

just googled it m8. not that hard

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