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3 years ago

5. Given that a 40.14 g sample of hydrated NiSO4•XH2O is reduced in mass to 2.14 g upon heating.

Chemistry

1 answer:

Ahat [919]3 years ago

4 0

<h3>Answer:</h3>

Value of X is 7

<h3>Explanation:</h3>

We are given;

Mass of the Hydrated sample as 40.14 g
Mass of the anhydrous salt as 22.14 g (Missing in the question)

We are required to determine the value of X in the hydrated sample, NiSO4•XH2O .

First, we determine the mass of the anhydrous salt

Mass of water of crystallization = Mass hydrate sample - Mass of anhydrous sample

= 40.14 g - 22.14 g

= 18.0 g

We can determine the value of X by determine simple number ratio of anhydrous compound and water molecules.

Determine the number of moles
Molar mass of NiSO₄ = 154.75 g/mol
Moles of NiSO₄ = 22.14 g ÷ 154.75 g/mol

= 0.1431 mole

Molar mass of water = 18.02 g/mol

Moles of water = 18.0 g ÷ 18.02 g/mol

= 1.00 mole

We can then determine the mole ratio.

Mole ratio = 0.1431 mole : 1.00 mole

= 0.1431 mole/0.1431 mole : 1.00 mole/0.1421 mole

= 1 : 7.03

= 1 : 7

Therefore, the formula of the hydrated salt is NiSO₄•7H₂O

Thus, the value of X is 7

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$2H_{2}O + Br_{2} + SO_{2} \rightarrow 2Br^{-} + SO^{2-}_{4} + 4H^{+}$

Hence, expression that represents relation between given reaction and Q will be as follows.

Q = $\frac{[Br^{-}]^{2}[SO^{2-}_{4}][H^{+}]^{4}}{[Br_{2}]P_{SO_{4}}}$

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As relation between pH and $[H^{+}]$ is as follows.

pH = -log $[H^{+}]$

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In disolution, the equilibrium will look like this:

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The equation above means that, one mol of lead (II) nitrate dissolved in 1L will yield one mol of Pb ions and 2 moles of NO3 ions, i.e. 3 moles total.

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The atomic weight of the elements in cisplatin is:

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