Which of the following is the best leaving group? (a) F– (b) Cl– (c) Br– (d) I–

Which of the following is the best leaving group?
(a) F–
(b) Cl–
(c) Br–
(d) I–
by

1 Answer

Answer :

I–
by

Related questions

From the elements: Cl, Br, F, O, Al, C, Li, Cs and Xe; choose the following: (a) The element with highest negative electron gain enthalpy. (b) The element with lowest ionization enthalpy. (c) The element with smallest ionic radius. (d) The element with six electrons in the valence shell. (e) The element which is a liquid at room temperature. (f)The element which belongs to zero group. (g) The elements which forms largest number of compounds.

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Last Answer : Ans. (a). The element chlorine (Cl) has the highest negative electron gain enthalpy. (b). The element cesium (Cs) has lowest ionization enthalpy. (c). The element fluorine F has lowest atomic radius. (d ... zero group (or group 18). (g). The element carbon (C) forms the largest number of compounds.

The increasing order of reactivity among group 1 elements is Li<Na<K<Rb<Cs whereas among the group 17 elements, it is F>Cl>Br>I. Explain.

Description : The increasing order of reactivity among group 1 elements is Li

Last Answer : Ans. In group 1 elements (alkali metals) the reactivity of the metals is mainly due to the electron releasing tendency of their atoms, which is related to ionization enthalpy, Since ... electron gain enthalpy. Since both of them decrease down the group, the reactivity therefore decreases.

Arrange the following order of the property indicated: (a). F, Cl, Br and I (negative electron gain enthalpy) (b). Mg, Al, Si and Na (ionization enthalpy) (c). C, N, O and F (second ionization enthalpy)

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Last Answer : Ans. (a). I

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Which has the smallest bond angle `X-S-X` in the given molecules ? (X=F, Cl, Br, I)

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Which of the following is the strongest nucleophile in an aqueous solution? (a) HO– (b) Cl– (c) Br– (d) I

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Last Answer : Answer : C

Which of the following is NOT oxidized by chlorine? w) F- (read: F minus) x) Br- (read: B - R minus) y) F2 (read: F - 2) z) I- (read: I minus)

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Which out of F or Cl has a more negative electron gain enthalpy?

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In \( III ^{ rd } \) group of salt analysis for cations \( NH _{4} Cl \) and \( NH _{4} OH \) are added as group reagents. Which of the following can be used instead of \( NH _{4} Cl \) ?(a) \( NaCl \)(b) \( \left( NH _{4}\right)_{2} SO _{4} \)(c) \( \left( NH _{4}\right)_{2} C _{2} O _{4} \)(d) \( NH _{4} NO _{3} \)

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The most electropositive elements among the following is : (1) Cs (2) Ca (3) Na (4) Br

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For the complex [Fe(en)2Cl2], Cl, (en = ethylene diamine), identify (i) the oxidation number of iron, (ii) the hybrid orbitals and the shape of the complex, (iii) the magnetic behaviour of the complex, (iv) the number of geometrical isomers, (v) whether there is an optical isomer also, and (vi) name of the complex. (At. no. of Fe = 26) \ -Chemistry

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