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3 years ago

8

Platinum crystallizes with the face-centered cubic unit cell. The radius of a platinum atom is 139 pm. Calculate the edge length

of the unit cell and the density of platinum in g>cm3.

1 answer:

horrorfan [7]3 years ago

3 0

Answer:

Length = 393pm, Density = 21.3 g/cm^3.

Explanation:

From the question above, we have the following parameters or data which is going to aid in solving the above Question.

=> The radius of a platinum atom = 139 pm.

Therefore, the length can be calculated by making use of the formula given below:

Length = 2 √( 2r) = 2 × √ (2 × 139 × 10^-12m ) = 393 × 10^-10 m = 393pm.

The density can be calculated by making use of the chemical formula given below:

Density = mass ÷ volume = (195.064/ 6.02 × 10^23) ÷ (3.93 × 10^-10/ 10^-2) = 21.3 g/cm^3.

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Answer:

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Explanation:

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Hence, change in temperature will be calculated as follows.

$\Delta T_{b} = (T_{b} - T^{o}_{b})$

= 374.24 K - 323 K

= 1.24 K

As molality is defined as the moles of solute present in kg of solvent.

Molality = $\frac{\text{weight of solute \times 1000}}{\text{molar mass of solute \times mass f solvent(g)}}$

Let molar mass of the solute is x grams.

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n = $\frac{\text{Molecular mass}}{\text{Empirical mass}}$

= $\frac{1321.29 g}{30 g/mol}$

= 44 mol

Thus, we can conclude that the formula of given material is $C_{44}H_{88}O_{44}$ .

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