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Mendeleeff said about eka-aluminium "If ...

Mendeleeff said about eka-aluminium "If I hold it in my hand, it will melt". Guess the reason.

A

The melting point of 'Ga' is `30.2^@`C

B

The melting point of 'Ge' is.`30.2^@`C

C

The melting point of 'Sc' is `30.2^@`C

D

The melting point of 'Al' is `30.2^@`C

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alpha - amino acids are high melting crystalline solids because of the zwitterion structure. They are moderately soluble in water. In acidic medium, alpha - amino acids exist as cations (I) and thus migrate towards cathode under the influence of an electric field. On the other hand, in alkaline medium, alpha - amino acids exist as anions (III) and thus migrate towards anode under the influence of an electric field. However, at some intermediate value of p^(H) , the concentration of the cationic form (I) and anionic form (III) will become equal and consequently the alpha - amino acid will exist primarily as the neutral dipolar ion (II). At this p^(H) , there would be no net migration of the amino acid in an electric field. This p^(H) at which there is no net migration of the amino acid under the influence of an applied electric field is called isoelectric point (pI). Each amino acid has a characteristic isoelectric point. The pH of an amino acid that does not have an ionisable side chain such as alanine isd average of pK_(a) values of the carboxyl group and the protonated amino group. H_(3)overset(+)(N)-overset("R")overset("|")("C")H-COOH overset(" "OH^(-)" ")underset(" "H^(+)" ")hArr H_(3)overset(+)(N)-underset("Zwitterion (II)")(overset("R")overset("|")("C")H)-COO^(-)overset(" "OH^(-)" ")underset(" "H^(+)" ")hArr underset((III))(overset(+)(N)-overset("R")overset("|")("C")H)-COO^(-) Further, the alpha - carbon of all the amino acids (except glycine) is chiral (asymmetric) and hence amino acids can exist in teo stereoisomeric forms i.e., D and L. However, all the nautrally occurring amino acids belong to the L - series. underset("L(-)Glyceraldehyde")(HO-overset("CHO ")overset("| ")underset(" "CH_(2)OH)underset("| ")("C ")-H)" " underset("L-Amino acid")(H_(2)N-overset("COOH")overset("| ")underset("R ")underset("| ")("C ")-H) In alanine, carboxyl group ionises at pK_(a1)=2.34 and ammonium ion at pK_(a2)=9.69 . The isoelectric point of the amino acid is at p^(H) .

alpha - amino acids are high melting crystalline solids because of the zwitterion structure. They are moderately soluble in water. In acidic medium, alpha - amino acids exist as cations (I) and thus migrate towards cathode under the influence of an electric field. On the other hand, in alkaline medium, alpha - amino acids exist as anions (III) and thus migrate towards anode under the influence of an electric field. However, at some intermediate value of p^(H) , the concentration of the cationic form (I) and anionic form (III) will become equal and consequently the alpha - amino acid will exist primarily as the neutral dipolar ion (II). At this p^(H) , there would be no net migration of the amino acid in an electric field. This p^(H) at which there is no net migration of the amino acid under the influence of an applied electric field is called isoelectric point (pI). Each amino acid has a characteristic isoelectric point. The pH of an amino acid that does not have an ionisable side chain such as alanine isd average of pK_(a) values of the carboxyl group and the protonated amino group. H_(3)overset(+)(N)-overset("R")overset("|")("C")H-COOH overset(" "OH^(-)" ")underset(" "H^(+)" ")hArr H_(3)overset(+)(N)-underset("Zwitterion (II)")(overset("R")overset("|")("C")H)-COO^(-)overset(" "OH^(-)" ")underset(" "H^(+)" ")hArr underset((III))(overset(+)(N)-overset("R")overset("|")("C")H)-COO^(-) Further, the alpha - carbon of all the amino acids (except glycine) is chiral (asymmetric) and hence amino acids can exist in teo stereoisomeric forms i.e., D and L. However, all the nautrally occurring amino acids belong to the L - series. underset("L(-)Glyceraldehyde")(HO-overset("CHO ")overset("| ")underset(" "CH_(2)OH)underset("| ")("C ")-H)" " underset("L-Amino acid")(H_(2)N-overset("COOH")overset("| ")underset("R ")underset("| ")("C ")-H) N - terminus of the peptide structure is on the

VGS PUBLICATION-BRILLIANT-CLASSIFICATION OF ELEMENTS-THE PERIODIC TABLES-EXERCISE
  1. Guess the atomic weight of middle element if the atomic weights ...

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  2. Ea2O3: EsO2 : GeO2 [ Ea = Eka aluminium, Es= Eka silicon]

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  3. Mendeleeff said about eka-aluminium "If I hold it in my hand, it will ...

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  4. Which of the following elements are not available at the time of Mende...

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  5. Which of the following element does not contain '3s' orbital ?

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  6. Why are lanthanides and actinides placed separately at the bot...

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  7. If 'He' is not a inert gas, it should be placed in the group.

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  8. n = 1: 1s ::n = 2: ………….

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  9. Guess the period if it has only '8' elements and K, L shells.

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  10. Which one shrinks in size than atom : i) Na^+ii) Na iii) Cl^- iv) CI

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  11. The ionization potential of 'Be' is more than 'B'. This is due to

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  12. Assertion (A) : The size of Na^+ ion is less than 'Na' atom. Reason (R...

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  13. The element at the bottom of a group would be expected to show ...

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  14. The outermost main shell of an element is 'M' shell. This element belo...

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  15. Give example where the electronic configuration of an element does not...

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  16. generally show less electronegative character.

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  17. The atomic radius of Cl than Cl^- atom.

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  18. cannot be decomposed into further substance by a physical or chemical ...

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  19. Which one shrinks in size than atom : i) Na^+ii) Na iii) Cl^- iv) CI

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  20. Atomic number of the element which has diffe rentiating electron enter...

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