CBSE 11TH CHEMISTRY - Online Test
Q1. The enthalpies of elements in their standard states are taken as zero. The enthalpy of formation of a compound
Answer : Option C
Explaination / Solution:
Enthapy of formation of a compound from elements in standard state can b +ve or –ve.
Q2. In which of the following substances will hydrogen bond be strongest?
Answer : Option A
Explaination / Solution:
Out of all H2O will form strongest hydrogen bonding due to high electronegativity of O.
Q3. Metal carbonates decompose on heating to give metal oxide and carbondioxide. Which of the metal carbonates is most stable thermally?
Answer : Option D
Explaination / Solution:
is very stable due to size compatibility factor . A larger cation can stablise a larger anion.Group 2 element become more thermally stable down the group.
Q4. In which of the following representations given below spatial arrangement of group/ atom different from that given in structure ‘A’?
Answer : Option A
Explaination / Solution:
No Explaination.
Q5. Dipole-dipole forces act between the molecules possessing permanent dipole. Ends of dipoles possess ‘partial charges’. The partial charge is
Answer : Option A
Explaination / Solution:
It is less than unit electronic charge.
Q6. One mole is the amount of a substance that contains as many particles or entities as there are atoms in
Answer : Option C
Explaination / Solution:
One mole is the amount of a substance that contains as many particles or entities as there are atoms in exactly 12 g of the isotope .
A mole of a substance always contains the same number of entities , no matter what the substance may be. In order to determine this number precisely , the mass of carbon -12 atom was determined by mass spectrometer and found to be equal to 1.992648 x 10-23 g. Knowing that one mole of carbon weighs 12 g . the number of atoms in it is equal to :
6.0221367 x 1023
Q7. The general formula of a cycloalkane is
Answer : Option B
Explaination / Solution:
Cycloalkanes have general formula of
Q8. What is the best description of the change that occurs when is dissolved in water?
Answer : Option C
Explaination / Solution:
Oxide ion donates a pair of electrons
Q9. The electron releasing tendency of the metals, zinc, copper and silver is in the order:
Answer : Option A
Explaination / Solution:
The electron releasing tendency of the metals, zinc, copper and silver is in the order Zn>Cu>Ag
This is according to the metal activity series or electrochemical series.
Q10. A transition metal ion exists in its highest oxidation state. It is expected to behave as
Answer : Option B
Explaination / Solution:
If the metal is at its highest oxidation state, then it will have no desire to loose more electrons. It will have the tendency to gain electron, and go to a lower oxidation state, i. e. it behaves like an oxidizing agent.
