Of the following which change will shift the reaction towards the product?
Increase in concentration of I
Decrease in concentration of I2
Increase in temperature
Increase in total pressure
Assertion : The free gaseous Cr atom has six unpaired electrons.
Reason: Half-filled s orbital has greater stability.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false.
Assertion : Nuclear binding energy per nucleon is in the order -
Reason : Binding energy per nucleon increases linearly with difference in number of neutrons and protons.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false.
Assertion : All F- S -F angle in SF4 is greater than 90° but less than 180°.
Reason : The lone pair-bond pair repulsion is weaker than bond pair-bond pair repulsion.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false.
Assertion : Effusion rate of oxygen is smaller than nitrogen.
Reason: Molar mass of nitrogen is smaller than oxygen.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false.
Which of the following is only acidic nature?
Be(OH)2
Mg(OH)2
B(OH)3
Al(OH)3
C.
B(OH)3
B(OH)3 in aqueous medium coordinates a molecule of water to form the hydrated species . In this species, B3+ ion, because of its small size, exercises a high polarizing power thereby pulling the sigma electron charge of the coordinated O atom towards itself. The coordinated oxygen, in turn, pulls the sigma electron charge of the OH bond of the attached H2O molecule towards itself. This facilitates the removal of H+ ion from the O- H bond, as shown below.
Thus the solution of B(OH)3 in water acts as a weak acid. That is why it reacts with NaOH solution to produce the sodium salt.
Which of the following imparts green colour to the burner flame?
B(OMe)3
Na(OMe)
Al(OPr)3
Sn(OH)2
The compound having only primary hydrogen atoms is
isobutene
2,3-dimethylbutene
cyclohexane
propyne