Answer:
The mole is important because it allows chemist to work with a subatomic world with macro world units and amount. Atoms molecules and formula units are very small and very difficult to work with usually. However the mole allows a chemist to work with amount large enough to use.
Answer:
2 Cr(s) + 3 Fe(NO3)2(aq) = 3 Fe(s) + 2 Cr(NO3)3(aq)
Explanation:
I balanced this chemical equation so that both sides are equal, meaning that the mass of reactants is equal to mass of products.
I believe it would be the first option. It forms iron oxide (rust) when exposed to moisture and air.
Answer:

Explanation:
Hello!
In this case, since the density is computed by dividing the mass of the substance by its occupied volume (d=m/V), we first need to realize that 0.8206 g/mL is the same to 0.8206 kg/L, which means we first need to compute the volume in L:

Then, solving for the mass in d=m/V, we get m=d*V and therefore the mass of gasoline in that full tank turns out:

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