The alpha particles that were fired at the gold foil were positively charged. ... These experiments led Rutherford to describe the atom as containing mostly empty space, with a very small, dense, positively charged nucleus at the center, which contained most of the mass of the atom, with the electrons orbiting the nucleus.
hope this helped
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 :
