Question

question 5 (1 point)
sulfur dioxide can be prepared by heating its constituent elements. when one mole of molten sulfur burns, it leads to the formation of so₂(g) and x kj of energy is produced. the balanced equation for the chemical reaction is
s₈(ℓ) + 8o₂(g) → 8so₂(g) dh = -2x kj
2s₈(ℓ) + 16o₂(g) → 16so₂(g) dh = 2x kj
s₈(ℓ) + 8o₂(g) → 8so₂(g) dh = x kj
2s₈(ℓ) + 16o₂(g) → 16so₂(g) dh = x kj
2s₈(ℓ) + 16o₂(g) → 16so₂(g) dh = -2x kj
question 6 (1 point)

Explanation:

Step1: Analyze the reaction type

Burning is an exothermic reaction, so $\Delta H$ should be negative.

Step2: Check the stoichiometry

Given that 1 mole of molten sulfur ($S_8$) burns. In the reaction $S_8(\ell)+8O_2(g)\to8SO_2(g)$, when 1 mole of $S_8$ reacts, if 1 mole of $S$ (since $S_8$ has 8 moles of $S$ atoms) gives $x$ kJ of energy, then for 8 moles of $S$ (from 1 mole $S_8$) the energy change is $- 8x/4=-2x$ kJ (because in the balanced equation for 1 mole $S_8$ forming 8 moles $SO_2$, and if per mole of $S$ (in terms of the basic reaction unit where 1 mole of atomic - equivalent $S$ gives $x$ kJ, but here we have 8 moles of atomic - equivalent $S$ in 1 mole $S_8$).

Answer:

A. $S_8(\ell)+8O_2(g)\to8SO_2(g)$ $\Delta H=-2x$ kJ