1
JEE Main 2021 (Online) 25th February Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
According to molecular orbital theory, the species among the following that does not exist is :
A
$${O_2}^{2 - }$$
B
$$B{e_2}$$
C
$$H{e_2}^ - $$
D
$$H{e_2}^ + $$
2
JEE Main 2021 (Online) 25th February Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
Complete combustion of 1.80 g of an oxygen containing compound (CxHyOz) gave 2.64 g of CO2 and 1.08 g of H2O. The percentage of oxygen in the organic compound is :
A
51.63
B
50.33
C
63.53
D
53.33
3
JEE Main 2021 (Online) 25th February Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The hybridization and magnetic nature of $${[Mn{(CN)_6}]^{4 - }}$$ and $${[Fe{(CN)_6}]^{3 - }}$$, respectively are :
A
sp3d2 and diamagnetic
B
d2sp3 and paramagnetic
C
sp3d2 and paramagnetic
D
d2sp3 and diamagnetic
4
JEE Main 2021 (Online) 25th February Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The major product of the following chemical reaction is :

JEE Main 2021 (Online) 25th February Morning Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 129 English
A
$$C{H_3}C{H_2}CHO$$
B
$$C{H_3}C{H_2}C{H_3}$$
C
$$C{H_3}C{H_2}C{H_2}OH$$
D
$${(C{H_3}C{H_2}CO)_2}O$$
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