Answer:
2.0 moles S
Explanation:
To find the number of moles of S, you need to convert the moles Na to moles S via the mole-to-mole ratio. This ratio is represented by the coefficients in the balanced equation. Because you wish to find moles S, you want to put this number in the numerator. Because you want to eliminate the moles Na, this number should be in the denominator.
2 Na + 1 S ---> Na₂S
4.0 moles Na 1 mole S
---------------------- x --------------------- = 2.0 moles S
2 moles Na
Answer:
irreversible changes
Explanation:
Most chemical changes are permanent and cannot be reversed. That is because a chemical change involves changing the molecular composition which can't be reversed. A common example of a chemical change would be burning wood. The wood burning into ash is changing the molecular composition of the wood transforming it to ash. Now can ash be changed back into wood? No, it is a "irreversible change."
Hope this helps.
Answer:
Stoichiometry measures these quantitative relationships, and is used to determine the amount of products and reactants that are produced or needed in a given reaction.
ΔH2 = - δH1 δH2 = - 2 x δH1 δH2 = 2 x <span>δ</span>H1
