to have the closest number rounded up
According to the density of the liquid, we can get the mass of liquid is 70*0.85=59.5 g. So the total mass is 59.5+60.75=120.25 g.
Answer:

Explanation:
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In this case, since vaporization is the processes by which a liquid goes to the gas phase, fusion by which a solid goes to liquid and deposition by which a gas goes to solid; we infer that the following set up relates the enthalpies associated to each process:

Because deposition goes from a state with more energy to a state with less energy, therefore it is negative; in such a way, by plugging in we obtain:

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The reaction represents the law of conservation of mass (a balanced chemical equation :
2NaN₃ → 2Na + 3N₂
<h3>Further explanation
</h3>
Conservation of mass applies to a closed system, where the masses before and after the reaction are the same, so balanced chemical equations show that mass is conserved in chemical reactions.
So we just have to look at the amount of each type of element present in the reactants and products must be the same
1. Hg + O₂ → HgO
not balanced, because element O not equal(2 in left, 1 in right)
2. 2NaN₃ → 2Na + 3N₂
balanced, because element in reactant and product are the same
Na, left = 2, right=2
N, left =2x3=6, right=3x2=6
3. C+O → CO₂
not balanced, because element O not equal(1 in left, 2 in right)
4. CH₄ + O₂ → CO₂ +H₂O
not balanced, because element O and H not equal