Science (English Medium) कक्षा ११ - CBSE Question Bank Solutions

Among the elements \[\ce{B, Al, C}\] and \[\ce{Si}\], which element has the most metallic character?

Arrange the elements \[\ce{N, P, O}\] and \[\ce{S}\] in the order of increasing non metallic character. Give reason for the arrangement assigned.

Among alkali metals which element do you expect to be least electronegative and why?

What is meant by the term average bond enthalpy? Why is there difference in bond enthalpy of \[\ce{O - H}\] bond in ethanol \[\ce{(C2H5OH)}\] and water?

The variation of pressure with volume of the gas at different temperatures can be graphically represented as shown in figure.

On the basis of this graph answer the following questions.

(i) How will the volume of a gas change if its pressure is increased at constant temperature?

(ii) At a constant pressure, how will the volume of a gas change if the temperature is increased from 200 K to 400 K?

Match the following gas laws with the equation representing them.

The state of a gas can be described by quoting the relationship between ______.

We know that the relationship between K_c and K_p is K_p = K_c (RT)^∆n What would be the value of ∆n for the reaction \[\ce{NH4Cl (s) ⇌ NH3 (g) + HCl (g)}\]

Why do beryllium and magnesium not impart colour to the flame in the flame test?

What is the correct order of decreasing stability of the following cations.

Covalent bond can undergo fission in two different ways. The correct representation involving a heterolytic fission of CH₃ – Br is:

Write structures of various carbocations that can be obtained from 2-methylbutane. Arrange these carbocations in order of increasing stability.

Match the intermediates given in Column I with their probable structure in Column II.

Which of the following practices will not come under green chemistry?

An alkene ‘A’ contains three C – C, eight C – H σ bonds and one C – C π bond. ‘A’ on ozonolysis gives two moles of an aldehyde of molar mass 44 u. Write IUPAC name of ‘A’.

An alkene ‘A’ contains three C–C, eight C–H σ bonds and one C–C π bond. ‘A’ on ozonolysis gives two moles of an aldehyde of molar mass 44 u. Write IUPAC name of ‘A’.

The following data are obtained when dinitrogen and dioxygen react together to form different compounds:-

(a) Which law of chemical combination is obeyed by the above experimental data?Give its statement.

(b) Fill in the blanks in the following conversions:

(i) 1 km = ______ mm = ______ pm

(ii) 1 mg = ______ kg = ______ ng

(iii) 1 mL = ______ L = _______ dm³

How do you express the bond strength in terms of bond order?

Compare the relative stability of the following species and indicate their magnetic properties;

`"O"_2, "O"_2^+, "O"_2^-`(superoxide), `"O"_2^(2-)`(peroxide)

Calculate the bond order of N₂, O₂, `"O"_2^+`and `"O"_2^-`?