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bogdanovich [222]
3 years ago
13

After you preform your experiment, you determine that the kf value for naphthalene is 6.91 °c/m . you are using 10g of naphthal

ene and added 1.0 g of your unknown. the the freezing point of the solvent decreased by 4.47 °c when the unknown was added. knowing this information, determine the molar mass of the unknown. g/mol
Chemistry
1 answer:
Masteriza [31]3 years ago
8 0
Answer is: molar mass of compound is 154,58 g/mol.<span>
m(</span>naphthalene<span>) = 10 g = 0,01 kg.
m(unknown compound) = 1,00 g.
</span>Δ<span>T (solution) = 4,47 °C.
Kf(</span>naphthalene) = 6,91°C/m<span>; cryoscopic constant.
M</span>(unknown compound) = Kf(naphthalene)· m(unknown compound) ÷ m(naphthalene)<span> · ΔT(solution).
M(xylene) = </span>6,91°C/m<span> · 1 g ÷ 0,01 kg · 4,47</span>°C<span>.
M(xylene) = 154,58 g/mol.</span>
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The percent yield of the reaction : 89.14%

<h3>Further explanation</h3>

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mass H₂O :

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hope this helps!




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