Answer:
igneous rocks are made from molten,and therefore rarely have fossils in them.Metamorphic rocks are squished,put under pressure,and get heated to the extreme,so it's very rare for fossils to survive in these conditions.
We subtract the enthalpies of the reactants from that of the products:
Since this is < 0, this is an exothermic reaction.
In the reaction Sn(s) + 2H+(aq) → Sn2+ (aq) + H2(g)
from this reaction, we get that Sn loses from 0 to 2 electrons so it's oxidized So it is the reducing agent.
and H gains from 0 to 1 electrons so, it's reduced so ∴ it is the oxidizing agent
2H₂₍g₎ + O₂ ₍g₎→ 2H₂O
138 mol H₂ × (2 mol H₂O ÷ 2 mol H₂)= 138 mol H₂O
64 mol O₂ × (2 mol H₂O ÷ 1 mol O₂)= 128 mol H₂O
128 mol H₂O
