The substituents R 1 and R 2 for nine peptides are listed in the table given below- How many of these peptides are positively charged at Ph -7-0 -Peptide R 1 R 2 I H H II H CH 3 III CH 2 COOH H IV CH 2 CONH 2 CH 24 NH 2 V CH 2 CONH 2 CH 2 CONH 2 VI CH 24 NH 2 CH 24 NH 2 VII CH 2 COOH CH 2 CONH 2 VII CH 2 OH CH 24 NH 2 IX CH 24 NH 2 CH 3

The amino acid remain completely in Zwitter ionic at its isoelectric point. nbsp; Amino acids with additional acidic group have then isoelec tric pH less than ...

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Standard XII

Chemistry

Amino Acids

The substitue...

Question

The substituents R₁ and R₂ for nine peptides are listed in the table given below. How many of these peptides are positively charged at Ph = 7.0? ___

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Solution

The amino acid remain completely in Zwitter ionic at its isoelectric point. Amino acids with additional acidic group have then isoelec tric pH less than 7.0 and increasing pH above isoelectric point makes them anionic.
On the other hand, amino acids with additional basic group have their isoelectric pH greater than 7.0 and decreasing pH below isoelectric point (by adding acid solution) makes them cationic. The given peptide with followings R₁ and R₂ are basic, will remain protonated (cationic) at pH = 7.0.Thus, 4 is the correct integer.

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Similar questions

Q. The substituents

R_{1}

, and

R_{2}

for nine peptides are listed in the table given below. How many of these peptides are positively charged at pH = 7.0?

$P e p t i d e$	$R_{1}$	$R_{2}$
I	$H$	$H$
II	$H$	$C H_{3}$
III	$C H_{2} C O O H$	$H$
IV	$C H_{3} C O N H_{2}$	${(C H_{2})}_{4} N H_{2}$
V	$C H_{2} C O N H_{2}$	$C H_{2} C O N H_{2}$
VI	${(C H_{2})}_{4} N H_{2}$	${(C H_{2})}_{4} N H_{2}$
VII	$C H_{2} C O O H$	$C H_{2} C O N H_{2}$
VIII	$C H_{2} O H$	${(C H_{2})}_{4} N H_{2}$
IX	${(C H_{2})}_{4} N H_{2}$	$C H_{3}$

Q. The substituents

R_{1}

and

R_{2}

for nine peptides are listed in the table given below. How many of these peptides are positively charged at pH=7.0?

Peptide	$R_{1}$	$R_{2}$
I	H	H
II	H	$C H_{3}$
III	$- C H_{2} C O O H$	H
IV	$- C H_{2} C O N H_{2}$	$(C H_{2})_{4} N H_{2}$
V	$- C H_{2} C O N H_{2}$	$- C H_{2} C O N H_{2}$
VI	$(C H_{2})_{4} N H_{2}$	$(C H_{2})_{4} N H_{2}$
VII	$- C H_{2} C O O H$	$- C H_{2} C O N H_{2}$
VIII	$- C H_{2} O H$	$(C H_{2})_{4} N H_{2}$
IX	$(C H_{2})_{4} N H_{2}$	$C H_{3}$

Q. The substituents R₁ and R₂ for nine peptides are listed in the table given below. How many of these peptides are positively charged at Ph = 7.0? ___

Match the column:

I	II	III
Heat generated	Is used to reduce effective resistance in a circuit	V = IR
Resistances in parallel	Proportional to the square of current
Resistivity	Gives relation between V and I
Ohm’s law	Depends on the material of the conductor

Q. Match the compounds in column I with the correct formula in column II.

Column I	Column II
a. hydrochloric acid	i. NaOH
b. slaked lime	ii. H₂SO₄
c. sulphuric acid	iii. H₂SO₃
d. nitric acid	iv. Ca(OH)₂
e. sodium hydroxide	v. H₂CO₃
f. calcium carbonate	vi. HCl
g. baking soda	vii. HNO₃
h. sulphurous acid	viii. CaCO₃
i. carbonic acid	ix. NaHCO₃

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The substituents R1 and R2 for nine peptides are listed in the table given below. How many of these peptides are positively charged at Ph = 7.0? ___

The substituents R₁ and R₂ for nine peptides are listed in the table given below. How many of these peptides are positively charged at Ph = 7.0? ___