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Lavneesh Rajput
Subject: Chemistry
, asked on 24/4/18
Solve this:
44.
Molecular orbital electronic configuration for X anion is
$KK(\sigma 2s{)}^{2}(\sigma *2s{)}^{2}\left(\mathrm{\pi}2{p}_{x}{)}^{2}(\mathrm{\pi}2{p}_{y}{)}^{2}\right(\sigma 2{p}_{z}{)}^{2}(\sigma *2{p}_{x}{)}^{1}\phantom{\rule{0ex}{0ex}}ThenanionXis\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}(a)N{}_{2}^{}(b)O{}_{2}^{}\phantom{\rule{0ex}{0ex}}(c)N{}_{2}^{2}(d)O{}_{2}^{2}$
Answer
1
Tarun Kumar
Subject: Chemistry
, asked on 23/4/18
which of the following is amphoteric oxide
a)V2O5,Cr2O3 b)Mn2O7,Cr2O3
c)CrO,V2O5 d)V2O5,V2O4
Answer
1
Lavneesh Rajput
Subject: Chemistry
, asked on 23/4/18
Solve this:
Q.5. Which one of the following ions will be colourless?
(a)
$L{a}^{3+}$
(b)
$N{d}^{3+}$
(c)
$P{r}^{3+}$
(d)
$T{i}^{3+}$
Answer
2
Muhammad Arafath R Z
Subject: Chemistry
, asked on 18/4/18
Atomic structure Online mains 2018:
Q. 30. The correct order of spinonly magnetic moments among the following is :
(atomic number : Mn=25, Co=27, Ni = 28, Zn=30)
Option
$1.{\left[NiC{l}_{4}\right]}^{2}{\left[CoC{l}_{4}\right]}^{2}{\left[MnC{l}_{4}\right]}^{2}{\left[ZnC{l}_{4}\right]}^{2}\phantom{\rule{0ex}{0ex}}2.{\left[ZnC{l}_{4}\right]}^{2}{\left[NiC{l}_{4}\right]}^{2}{\left[CoC{l}_{4}\right]}^{2}{\left[MnC{l}_{4}\right]}^{2}\phantom{\rule{0ex}{0ex}}3.{\left[CoC{l}_{4}\right]}^{2}{\left[MnC{l}_{4}\right]}^{2}{\left[NiC{l}_{4}\right]}^{2}{\left[ZnC{l}_{4}\right]}^{2}\phantom{\rule{0ex}{0ex}}4.{\left[MnC{l}_{4}\right]}^{2}{\left[CoC{l}_{4}\right]}^{2}{\left[NiC{l}_{4}\right]}^{2}{\left[ZnC{l}_{4}\right]}^{2}$
Answer
1
Jeneeta Eliza John
Subject: Chemistry
, asked on 18/4/18
Isn't AgBr used in black and white photography?
Q. In black and white photography, the developed film is fixed by washing with
(1) AgBr solution
(2) Hypo solution
(3)
$N{a}_{2}{S}_{4}{O}_{6}$
solution
(4)
$Fe{C}_{2}{O}_{4}$
solution
Sol. Answer (2)
In black and white photography hypo solution is used.
Answer
2
Jeneeta Eliza John
Subject: Chemistry
, asked on 18/4/18
Isn't Mn2+ also colourless?
Q.13. Which of the following is not coloured?
(1)
$M{n}^{2+}$
(2)
$C{r}^{3+}$
(3)
$Z{n}^{2+}$
(4)
$C{u}^{2+}$
Sol. Answer (3)
$Z{n}^{2+}$
does not show any colour because no any transition is possible there due to
$3{d}^{10}$
configuration.
Answer
3
Jeneeta Eliza John
Subject: Chemistry
, asked on 18/4/18
Shouldn't the answer be (1)
Q.9. The correct statement
(1) Green vitriol and blue vitriol are isomorphus
(2)
$KMn{O}_{4}and{K}_{2}C{r}_{2}{O}_{7}$
are coloured due to dd transitions
(3)
$C{u}_{2}C{l}_{2}andA{g}_{2}S$
are coloured
(4) Upon strong heating paramagnetic gases are evolved by
$NaN{O}_{3}andAgN{O}_{3}$
Sol. Answer (4)
Answer
1
Jeneeta Eliza John
Subject: Chemistry
, asked on 18/4/18
Doesn't all the other elemts also have d electrons? Why is the answer Ni?
Q.3. The element having lowest
$I{E}_{1}$
(1) Fe
(2) Co
(3) Ni
(4) Cu
Sol. Answer (3)
Ni has the lowest
$I{E}_{1}$
value because of the sheilding of 3d electrons.
Answer
1
Jeneeta Eliza John
Subject: Chemistry
, asked on 18/4/18
How to decide the 16th answer? Ans is (3):
16. Which is coloured because of dd transition ?
(1) KMnO
_{4}
(2) K
_{2}
CrO
_{4}
(3) CoCl
_{3}
(4) All of these.
Answer
2
Rayyan Mansuri
Subject: Chemistry
, asked on 14/3/18
please answer question no. 6
Q6). Give the IUPAC name of the product obtained when Phenol is oxidized by chromic acid. (Na
_{2}
_{ }
Cr
_{2}
_{ }
O
_{z}
+ Conc. H
_{2}
SO
_{4}
).
(A) Cyclohexanone
(B) Cyclohexa  2, 5  diene  1, 4 dione
(C) Cyclohexa  1, 4  dione
(D) Cyclohexa  1, 4  diene  2, 5  dione
Answer
2
Yatharth
Subject: Chemistry
, asked on 12/3/18
Is mn2+ colourless
Answer
1
Varnika Dhiman
Subject: Chemistry
, asked on 12/3/18
Explain why the configurations are like this for these elements and for all the elements of this series.
Answer
1
Varnika Dhiman
Subject: Chemistry
, asked on 11/3/18
Kindly explain this to me. What are these values, what do we mean by saying if an element has very less negative value or more negative value, etc, etc..
Element

Sc
Ti
V
Cr
MN
Fe
Co
Ni
Standard Electrode
M
^{2}
^{+}
/M

1.63
1.18
0.90
1.18
0.44
0.28
0.25
Potential E
^{o}
/V
M
^{3}
^{+}
/M
^{2}
^{+}

0.37
0.26
0.41
+1.57
+0.77
+1.97

Answer
1
Varnika Dhiman
Subject: Chemistry
, asked on 11/3/18
How can we write electronic configuration of elements in the form 2, 8, 18.. ?!..
Kindly write the same for Br, Ti, Fe, Zn.
[Kindly answer all of these here only, as they are so short.]
Answer
1
Varnika Dhiman
Subject: Chemistry
, asked on 11/3/18
Why electronic configuration is not 5d5 6s1?!.. (as in case of Cr & Mo)..
Answer
1
1
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What are you looking for?
44. Molecular orbital electronic configuration for X anion is
$KK(\sigma 2s{)}^{2}(\sigma *2s{)}^{2}\left(\mathrm{\pi}2{p}_{x}{)}^{2}(\mathrm{\pi}2{p}_{y}{)}^{2}\right(\sigma 2{p}_{z}{)}^{2}(\sigma *2{p}_{x}{)}^{1}\phantom{\rule{0ex}{0ex}}ThenanionXis\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}(a)N{}_{2}^{}(b)O{}_{2}^{}\phantom{\rule{0ex}{0ex}}(c)N{}_{2}^{2}(d)O{}_{2}^{2}$
a)V2O5,Cr2O3 b)Mn2O7,Cr2O3
c)CrO,V2O5 d)V2O5,V2O4
Q.5. Which one of the following ions will be colourless?
(a) $L{a}^{3+}$
(b) $N{d}^{3+}$
(c) $P{r}^{3+}$
(d) $T{i}^{3+}$
Q. 30. The correct order of spinonly magnetic moments among the following is :
(atomic number : Mn=25, Co=27, Ni = 28, Zn=30)
Option
$1.{\left[NiC{l}_{4}\right]}^{2}{\left[CoC{l}_{4}\right]}^{2}{\left[MnC{l}_{4}\right]}^{2}{\left[ZnC{l}_{4}\right]}^{2}\phantom{\rule{0ex}{0ex}}2.{\left[ZnC{l}_{4}\right]}^{2}{\left[NiC{l}_{4}\right]}^{2}{\left[CoC{l}_{4}\right]}^{2}{\left[MnC{l}_{4}\right]}^{2}\phantom{\rule{0ex}{0ex}}3.{\left[CoC{l}_{4}\right]}^{2}{\left[MnC{l}_{4}\right]}^{2}{\left[NiC{l}_{4}\right]}^{2}{\left[ZnC{l}_{4}\right]}^{2}\phantom{\rule{0ex}{0ex}}4.{\left[MnC{l}_{4}\right]}^{2}{\left[CoC{l}_{4}\right]}^{2}{\left[NiC{l}_{4}\right]}^{2}{\left[ZnC{l}_{4}\right]}^{2}$
Q. In black and white photography, the developed film is fixed by washing with
(1) AgBr solution
(2) Hypo solution
(3) $N{a}_{2}{S}_{4}{O}_{6}$ solution
(4) $Fe{C}_{2}{O}_{4}$ solution
Sol. Answer (2)
In black and white photography hypo solution is used.
Q.13. Which of the following is not coloured?
(1) $M{n}^{2+}$
(2) $C{r}^{3+}$
(3) $Z{n}^{2+}$
(4) $C{u}^{2+}$
Sol. Answer (3)
$Z{n}^{2+}$ does not show any colour because no any transition is possible there due to $3{d}^{10}$ configuration.
Q.9. The correct statement
(1) Green vitriol and blue vitriol are isomorphus
(2) $KMn{O}_{4}and{K}_{2}C{r}_{2}{O}_{7}$ are coloured due to dd transitions
(3) $C{u}_{2}C{l}_{2}andA{g}_{2}S$ are coloured
(4) Upon strong heating paramagnetic gases are evolved by $NaN{O}_{3}andAgN{O}_{3}$
Sol. Answer (4)
Q.3. The element having lowest $I{E}_{1}$
(1) Fe
(2) Co
(3) Ni
(4) Cu
Sol. Answer (3)
Ni has the lowest $I{E}_{1}$ value because of the sheilding of 3d electrons.
16. Which is coloured because of dd transition ?
(1) KMnO_{4} (2) K_{2}CrO_{4}
(3) CoCl_{3} (4) All of these.
Q6). Give the IUPAC name of the product obtained when Phenol is oxidized by chromic acid. (Na_{2}_{ }Cr_{2}_{ }O_{z} + Conc. H_{2}SO_{4}).
(A) Cyclohexanone
(B) Cyclohexa  2, 5  diene  1, 4 dione
(C) Cyclohexa  1, 4  dione
(D) Cyclohexa  1, 4  diene  2, 5  dione
Kindly write the same for Br, Ti, Fe, Zn.
[Kindly answer all of these here only, as they are so short.]