Answer:
chemical energy is stored in the wood before combustion.
Answer:
1120 L.
Explanation:
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In this case, as no conditions of pressure of temperature are given for this problem, we can assume that the scuba diver dives at STP (1 atm and 273.15 K), which means that 1 mole of air would occupy a volume of 22.4 L.
In such a way, since she needs 50.0 moles of air, the following ratio is useful to compute the size (volume) of the tank she needs:

Thereby, we plug in to obtain:

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Answer:
N - 1s²2s²2p³
Explanation:
Nitrogen is located in the p-block of the periodic table (groups 13-18) and is on the 2nd period.
The 2nd period tells us the principal energy level (a quantum number) is n = 2. Therefore, it must have already filled up the 1s sublevel.
The groups 13-18 on period 2 tells us that the 2s sublevel is also filled.
Nitrogen is located in Group 15. That means that there are 3 electrons that have filled the 2p sublevel, out of a possible 6.
Therefore, our electron configuration is 1s²2s²2p³
2p³ (Shorthand Config)
[He] 2s²2p³ (Noble Gas Config)
Gypsum has the same hardness as a fingernail