CBSE 11TH CHEMISTRY - Online Test
Q1. One mole of magnesium nitride on the reaction with an excess of water gives:
Answer : Option C
Explaination / Solution:
on hydrolysis roduces two moles of ammonia.
Q2.
The geometry of a complex species can be understood from the knowledge of type of hybridisation of orbitals of central atom. The hybridisation of orbitals of central atom in and the geometry of the complex are respectively
Answer : Option D
Explaination / Solution:
In B is tetrahedrally surrounded by 4 ion.
Q3. Catenation i.e., linking of similar atoms depends on size and electronic configuration of atoms. The tendency of catenation in Group 14 elements follows the order:
Answer : Option D
Explaination / Solution:
Catenation property decreases down the group as size of the atom increases.
Q4. Silicon has a strong tendency to form polymers like silicones. The chain length of silicone polymer can be controlled by adding
Answer : Option B
Explaination / Solution:
SiCl has only one Cl and (can react once) to forms only dimer thus it is used as chain controlling agent (terminate the polymerisation process).
Q5. In the structure of diborane
Answer : Option B
Explaination / Solution:
has 4 terminal H attached to B atoms ans all these lie I the same plane. Also in diborane we have 2 bridging hydrogen(3 centre 2 electron ) which lie perpendicular to the plane.
Q6. Quartz is extensively used as a piezoelectric material, it contains ___________.
Answer : Option C
Explaination / Solution:
Quartz contains Si. [Piezoelectric materials produces electricity when pressure is applied]
Q7. The linear shape of is due to _________.
Answer : Option C
Explaination / Solution:
In () hybridisation of C is sp so due to pЛ –pЛ bonding it is linear. Further carbon is sp hybridised, and have linear structure.
Q8. The reason for small radius of Ga compared to Al is _______.
Answer : Option C
Explaination / Solution:
due to screening effect size of Ga< Al as in Ga d-electrons are present which have poor shielding effect so nuclear charge increases and size decreases.
Q9. Cement, the important building material is a mixture of oxides of several elements. Besides iron and sulphur, oxides of elements of which of the group (s) are present in the mixture?
Answer : Option B
Explaination / Solution:
Main Composition of Portland cement are: lime (CaO) (group 2), silica (SiO 2)(group 14) and alumina (Al 2O 3).(group 13)
Cement is a heavy powder of calcium aluminates and silicates
Q10. Dry ice is
Answer : Option A
Explaination / Solution:
Dry ice is solid CO2.
Solid CO2 sublimates. Thus it does not wet anything and called dry ice.
