∆H for given reaction -847kJ
- As it's negative reaction is exothermic
So
2 mol of Al releases 847KJ heat
4 mol Al releases
∆H=-1694KJ
They mainly store materials for other cells to use.
Nitrogen is the chemical element with the symbol N and atomic number 7. ... At standard temperature and pressure, a colourless and odorless atomic gas with the formula N. nitrogen forms about 78% of Earth's atmosphere.
Answer:

Explanation:
Hello!
In this case, as we know the mass of the total sample, we can first compute the mass of oxygen:

Next, we compute the moles of each element:

Now, we divide the moles by 0.184 moles, the fewest ones, to obtain:

Therefore, the empirical formula is:

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