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Sangeeta Jha
Subject: Chemistry
, asked on 22/5/18
plz explain with chemical reactions
43
.
Na
→
H
2
O
A
→
CO
2
B
→
SO
2
C
→
Na
2
S
+
I
2
D
The
compound
D
is
:
-
1
Na
2
SO
4
2
Na
2
S
4
O
6
3
Na
2
S
2
O
5
4
Na
2
S
2
O
3
Answer
1
Dharunika Vijayakumar
Subject: Chemistry
, asked on 18/5/18
chemical formula of nitrochalk
Answer
3
Shivam Sharma
Subject: Chemistry
, asked on 16/5/18
Why there is no covalent bond between molecules of non metals?
Answer
1
Bhavya Jain
Subject: Chemistry
, asked on 15/5/18
Please tell me how to do this question on electronic configuration. (Also do 58 if possible, but its optional)
Q58. A dye absorbs light ray of wavelength (
λ
) 4530 Å and re-emits radiation of wavelength 5080 Å. If we assume that 47% of energy absorbed is emitted, then the ratio of quanta emitted and absorbed is
a. 0.231 b. 0.527
c. 0.412 d. 0.612
Q59. On the basis of electronic configuration, if the ion X
3–
has 14 electrons, then the number of electrons present in X
2
+
is
a. 16 b. 14
c. 12 d. 18
Answer
1
Prerna Varshney
Subject: Chemistry
, asked on 23/4/18
Question no 6 &7 give reason for your answer
6. Which of the following represents correct decreasing order of polarity?
(a) NH
3
> PH
3
> AsH
3
>SbH
3
(b) NH
3
> SbH
3
> AsH
3
> PH
3
(c) SbH
3
> AsH
3
> PH
3
> NH
3
(d) NH
3
> AsH
3
> SbH
3
> NH
3
7. The species having maximum stability is
(a) CN
+
(b) CN (c) CN
-
(d) ON
Answer
2
Shri Ganesh
Subject: Chemistry
, asked on 20/4/18
please help me solve this
Q. Based on the following reaction identify alkene A
A
→
O
3
(
H
2
O
)
Zn
2
HCHO
+
CHO
|
CHO
CH
2
||
1. CH
3
– C–CH
3
2. CH
2
= CH – CH – CH
2
3. CH
3
– CH = CH – CH
3
4. CH
3
– CH
2
– CH = CH
2
Answer
1
Prerna Varshney
Subject: Chemistry
, asked on 20/4/18
The number of types of bonds between two carbon atoms in calcium carbide is
(a) one sigma, two pi
(b) one sigma, one pi
(c) two sigma, one pi
(d) two sigma, two pi
Answer
1
Muhammad Arafath R Z
Subject: Chemistry
, asked on 18/4/18
P block online 2018 main
Q.16
Lithium aluminium hydride reacts with silicon tetrachloride to form :
1. LiH, AlCl
3
and SiCl
2
2. LiCl, AlCl
3
and SiH
4
3. LiH, AlH
3
and SiH
4
4. LiCl, AlH
3
and SiH
4
Answer
1
Anuj
Subject: Chemistry
, asked on 17/4/18
Increasing order of bond formation tendency among the following is? Si-O Cl-O P-O S-O
Answer
1
Laieeqa
Subject: Chemistry
, asked on 16/4/18
Solve this:
Q. Conversion of oxygen into ozone is non-spontaneous at
(1) high temperature
(2) low temperature
(3) all temperatures
(4) room temperature
Answer
2
Archana
Subject: Chemistry
, asked on 28/3/18
can a redox reaction be like this?
Q.(4)
X
e
F
2
+
P
F
5
→
X
e
F
+
P
F
6
-
Answer
1
Ashrita Mishra
Subject: Chemistry
, asked on 24/3/18
what is meant by intermediate oxidation state?
Answer
1
Rayyan Mansuri
Subject: Chemistry
, asked on 14/3/18
please ignore the markings done with blue pen and answer it.
Answer
2
Rayyan Mansuri
Subject: Chemistry
, asked on 14/3/18
Give answer according to three marks of the following question.
Q)Write molecular formula and structural formula of the following substances
a phosphonic acid
b oleum
c perbromic acid
Answer
3
Mallika Subramanian
Subject: Chemistry
, asked on 14/3/18
When Cl2 reacts with F2 why is ClF3 formed and not FCl3?
Can the answer be:
This is because in interhalogen compounds the central atom must be the more electropositive and bigger element. Fluorine has the smallest size and is the most electronegative element. Fluorine exhibits only one oxidation state that is -1 and therefore cannot be the central atom in interhalogen compounds.
Answer
3
1
2
3
4
5
Next
What are you looking for?
Q58. A dye absorbs light ray of wavelength () 4530 Å and re-emits radiation of wavelength 5080 Å. If we assume that 47% of energy absorbed is emitted, then the ratio of quanta emitted and absorbed is
a. 0.231 b. 0.527
c. 0.412 d. 0.612
Q59. On the basis of electronic configuration, if the ion X3– has 14 electrons, then the number of electrons present in X2+ is
a. 16 b. 14
c. 12 d. 18
6. Which of the following represents correct decreasing order of polarity?
(a) NH3 > PH3 > AsH3 >SbH3
(b) NH3 > SbH3 > AsH3 > PH3
(c) SbH3 > AsH3 > PH3 > NH3
(d) NH3 > AsH3 > SbH3 > NH3
7. The species having maximum stability is
(a) CN+ (b) CN (c) CN- (d) ON
Q. Based on the following reaction identify alkene A
CH2
||
1. CH3 – C–CH3
2. CH2 = CH – CH – CH2
3. CH3 – CH = CH – CH3
4. CH3 – CH2 – CH = CH2
(a) one sigma, two pi
(b) one sigma, one pi
(c) two sigma, one pi
(d) two sigma, two pi
Q.16 Lithium aluminium hydride reacts with silicon tetrachloride to form :
1. LiH, AlCl3 and SiCl2
2. LiCl, AlCl3 and SiH4
3. LiH, AlH3 and SiH4
4. LiCl, AlH3 and SiH4
Q. Conversion of oxygen into ozone is non-spontaneous at
(1) high temperature
(2) low temperature
(3) all temperatures
(4) room temperature
Q.(4)
Q)Write molecular formula and structural formula of the following substances
a phosphonic acid
b oleum
c perbromic acid
Can the answer be:
This is because in interhalogen compounds the central atom must be the more electropositive and bigger element. Fluorine has the smallest size and is the most electronegative element. Fluorine exhibits only one oxidation state that is -1 and therefore cannot be the central atom in interhalogen compounds.