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3 years ago

Someone pls pls pls help me with this question.

Chemistry

1 answer:

Arisa [49]3 years ago

3 0

$\rm{\pink{\underline{\underline{\blue{REASON:-}}}}}$

⭐ Elements in which the last electron enters any one of the five d-oribitals of their respective penultimate shells are called as d-block elements .

⭐ But the last electron of Zn , Cd , Hg and Cn enters in the s-oribital of their respective ultimate shells rather than the d-oribitals of their respective penultimate shells . Therefore, these elements cannot be regarded as d-block elements .

☃️ But properties of these elements resemble to the d-block elements rather than s-block elements .

☃️ Therefore, to make the study of periodic classification of elements more rational, they are studied along with d-block elements .

✍️ Thus on the basis of properties all transition elements are d- block elements, but on the basis of electronic configuration all d -block elements are not transition elements .

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Answer: The entropy change of the surroundings will be -17.7 J/K mol.

Explanation: The enthalpy of vapourization for 1 mole of acetone is 31.3 kJ/mol

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3 years ago

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A) For balanced chemical equation: 2HgO(s) → 2Hg(l) + O₂(g).

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2) Mole ratio 2: n(HgO) : n(O₂) = 2 : 1.

3) Mole ratio 3: n(Hg) : n(O₂) = 2 : 1.

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2) Mole ratio 2: n(NH₃) : n(N₂) = 4 : 5.

3) Mole ratio 3: n(NH₃) : n(H₂O) = 4 : 6 (2 : 3).

4) Mole ratio 4: n(NO) : n(N₂) = 6 : 5.

5) Mole ratio 5: n(NO) : n(H₂O) = 6 : 6 (1 :1).

6) Mole ratio 6: n(N₂) : n(H₂O) = 5 : 6.

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