CBSE 11TH CHEMISTRY - Online Test
Q1. Which of the following statements about Hydrogen bond incorrect?
Answer : Option C
Explaination / Solution:
Hydrogen atom covalently bonded to highly electronegative atom such as N,O experience electrostatic field of another highly electronegative atom due to which a partial positive charge is developed on H atom.
Q2. Which of these is not a characteristic of aromatic Hydrocarbons?
Answer : Option B
Explaination / Solution:
aromatic hydrocarbon are not open chained. They are ring structures.they contain one or more benzene rings either fused or isolated in their molecules.
Q3. Mendeleev proposed that some of the elements were still undiscovered and, therefore, left several gaps in the table. He left the gap under aluminium and a gap under silicon, and called these elements Eka-Aluminium and Eka-Silicon. These were later discovered and named
Answer : Option C
Explaination / Solution:
Mendeleev arranged the elements according to their atomic weights. He corrected the atomic weights of few exisiting elements to explain their chemical and physical behaviour. Moreover, he felt that few elements are still to be discovered, so he left empty spaces for them in his periodic table. Two such elements whose properties he predicted; and were later discovered are Gallium and Germanium respectively.
Q4. According to first law of thermodynamics ΔU = q + w, where
Answer : Option B
Explaination / Solution:
In thermodynamics q=+ve when heat is supplied to the system. And w=+ve when work is done on the system while when work is done by the system w is taken as –ve.
Q5. in the Thomson Model of Atom
Answer : Option D
Explaination / Solution:
- J. J. Thomson, who discovered the electron in 1897, proposed the plum pudding model of the atom in 1904 before the discovery of the atomic nucleus in order to include the electron in the atomic model.
- In Thomson's model, the atom is composed of electrons surrounded by a soup of positive charge to balance the electrons' negative charges, like negatively charged "plums" surrounded by positively charged "pudding".
- The 1904 Thomson model was disproved by Hans Geiger's and Ernest Marsden's 1909 gold foil experiment.
Q6. Tropospheric and stratospheric pollution are actually the components of :
Answer : Option C
Explaination / Solution:
Tropospheric and stratospheric pollution is the pollution associated with tropospheric and stratospheric layers of atmosphere so they are components of atmospheric pollution.
Q7. The three isotopes of hydrogen in terms of chemical properties show one of the following properties
Answer : Option D
Explaination / Solution:
Isotopes difference in their rate of reaction.
Q8. The number of dots around the Lewis symbols for the elements represent
Answer : Option A
Explaination / Solution:
Gilbert N. Lewis is widely known for his use of simple symbolic representations of elements that show valence electrons as dots.
The Lewis electron-dot symbols focus on the electrons in the highest principal energy level in the atom, the valence electrons.
After all, these are the electrons that participate in chemical reactions. Lewis electron-dot symbols work well for the representative elements.
Q9. Calcium and Magnesium belong to the category of
Answer : Option B
Explaination / Solution:
calcium and megnesium are 2nd group element of periodic table which are obtaine on earth in the form ore, their oxides and hydroxide are alkaline in nature so they are alkaline earth metals
Q10. The IUPAC name for
Answer : Option A
Explaination / Solution:
1-Chloro-4-methyl-2-nitrobenzene is the iupac name of the given compound.
