The volume of H₂ evolved at NTP=0.336 L
<h3>Further explanation</h3>
Reaction
Decomposition of NH₃
2NH₃ ⇒ N₂ + 3H₂
conservation mass : mass reactants=mass product
0.28 NH₃= 0.25 N₂ + 0.03 H₂
2 g H₂ = 22.4 L
so for 0.03 g :

A hypothesis is given to explain a phenomena which has not been
explained till then.
it can be supported by an experiment if that experiment gets the other
results regarding that particular phenomena in agreement with that being
predicted by the hypothesis
N₂, H₂, NH₃ are present in the reaction mixture when equilibrium has been obtained.
Balanced chemical reaction: 3H₂ + N₂ ⇄ 2NH₃
Hydrogen (H₂ ) and nitrogen (N₂) are reactants.
Ammonia (NH₃) is product of the reaction.
Reaction goes in both direction, both reactants and product are present.
The amount of substance of reactants and products of reaction do not change when chemical reaction is in chemical equilibrium.
In a chemical reaction, chemical equilibrium is the state in which both reactants and products are present in concentrations which not change with time.
Speed of direct and irreversible chemical reaction are equal.
More about equilibrium: brainly.com/question/25651917
#SPJ4