CBSE 11TH CHEMISTRY - Online Test
Q1. Carbon monoxide is one of the most dangerous air pollutants and is produced as a result of :
Answer : Option D
Explaination / Solution:
Carbon monoxide is produced by incomplete combustion of carbon, firewood, petrol.
The reaction is as follows :
2C + O2 -----> 2CO
Q2. hydrogen compounds of non-metals are volatile compounds because
Answer : Option C
Explaination / Solution:
Covalent hydrides :They are formed when hydrogen molecule reacts with the p block elements. The most common examples, in this case, are CH4 and NH3. The hydrogen compounds formed with non-metals are also called hydrides. They are covalent and volatile compounds.
Q3. H.O.H bond angle in water is
Answer : Option C
Explaination / Solution:
Due to presence of two lone pairs on O in H2O bond angle reduce to 104.50 from 1090.
Q4. The general electronic configuration of alkali metals is
Answer : Option D
Explaination / Solution:
The general electronic configuration of alkali metals is ns1 as their outer most electron enters the S orbital and they have only on electon in their velence shell.
Q5.
Straight or branched chain compounds, for example, the below ones are called
Answer : Option C
Explaination / Solution:
They are straight chain compounds known as aliphatic comounds.
Q6. According to Avogadro Law equal volumes ofall gases at the same temperature and pressure should contain ---------- number of molecules .
Answer : Option C
Explaination / Solution:
Avogadro's law states that " equal volumes of all gases at same temperature and pressure contain equal number of molecules. "
Q7. Which of the following is the correct ideal gas law
Answer : Option D
Explaination / Solution:
PV=nRT is the correct Ideal Gas equation.
Here, P : Pressure
V : Volume
n : Number of Moles
R : Universal Gas Constant
T : Temperature
Q8. The aqueous solution of sugar does not conduct electricity. However, when sodium chloride is added to water, it conducts electricity. How will you explain this statement on the basis of ionisation and how is it affected by concentration of sodium chloride?
Answer : Option B
Explaination / Solution:
Sugar being a non-electroyte, does not ionize in water, whereas NaCl ionizes completely in water and produce Na+ and Cl- ions, which help in the conduction of electricity and when concentration of NaCl is increased , more Na+ and Cl- ions will be produced, hence conductance increases.
Q9. Stereoisomeric alkenes due to different arrangement of atoms or groups in space are referred to as
Answer : Option A
Explaination / Solution:
Isomers which have the same structural formulae but difffer in the relative spatial arrangements of atoms or groups around the double bond are called geometric isomers.athus geometrical isomers are atype of stereoisomers.
Q10. All combustion reactions, which make use of elemental dioxygen, as well as other reactions involving elements other than dioxygen are:
Answer : Option B
Explaination / Solution:
A combination reaction (also known as a synthesis reaction) is a reaction where two or more elements or compounds (reactants) combine to form a single compound (product). Such reactions may be represented by equations of the following form: X + Y → XY.
