HSC Science (Electronics) इयत्ता ११ वी - Maharashtra State Board Question Bank Solutions for Chemistry

Which properties of solvents are useful for solvent extraction?

Why should spotting of mixture be done above the level of mobile phase?

Define the Saturated solution.

Define Solvent extraction

List the properties of solvents which make them suitable for crystallization.

Select and write the most appropriate alternatives from the given choices.

Valence Shell Electron Pair repulsion (VSEPR) theory is used to predict which of the following:

Give four uses of adsorption.

Explain with example α - decay.

What is the difference between an α-particle and helium atom?

The half-life of ²⁴Na is 900 minutes. What is its decay constant?

How many α and β-particles are emitted in the transmutation \[\ce{^232_90Th -> ^208_82Pb}\]?

How many particles are emitted by 0.1 g of ²²⁶Ra in one year?

Find out the most stable species from the following. Justify 

`dot"CH","CH"_3-dot"CH" - "CH"_3,` \[\begin{array}{cc}\ce{CH3 -\dot{C} - CH3}\\
|\phantom{.}\\\phantom{..}\ce{CH3}\end{array}\]

Find out the most stable species from the following. Justify.

`bar"C""H"_3, bar"C""H"_2"Br", bar"C""Br"_3`

Find out the most stable species from the following. Justify.

\[\ce{\overset{+}{C}H3, \overset{+}{C}H2Cl, \overset{+}{C}Cl3}\]

Identify the α-carbons in the following species and give the total number of α-hydrogen.

\[\ce{CH_3 - CH_2 - \overset{⊕}{C}H-CH_2 - CH_3}\]

Identify the α - carbons in the following species and give the total number of α-hydrogen.

Identify the α-carbon in the following species and give the total number of α-hydrogens.

\[\ce{CH2 = CH - CH2 - CH3}\]

Draw a resonance structure of the following:

Phenol

Draw a resonance structure of the following:

Benzaldehyde