Chemistry - Online Test

Q1. Metal halides are found in lakes and seas because
Answer : Option A
Explaination / Solution:

Metal halides are soluble in water.

Q2. It has been found that the pH of a 0.01M solution of an organic acid is 4.15.Calculate the concentration of the anion, the ionization constant of the acid and its 
Answer : Option D
Explaination / Solution:

Ka = and pH=-log(Cα) and pKa=-logKa

Q3. The reagent used to distinguish between H2O2 and O3 is
Answer : Option B
Explaination / Solution:

H2O2 can decolorize the color of KMnO4.
Q4. Which of the following polymers have tetrafluoroethene monomer units?
Answer : Option B
Explaination / Solution:

Teflon is used in making non stick utensil surface.

Q5. Consider the elements: Cs, Ne, I and F. Identify the element(s) that exhibits only Positive oxidation state
Answer : Option C
Explaination / Solution:

Cs is alkali metal so will show positive oxidation state of +1.

Q6. The unit cell of a substance has cations A+ at the corners of the unit cell and the anions B – in the center. The simplest formul of the substance is
Answer : Option D
Explaination / Solution:

Contribution of A=  Contribution of B = 1. Formula is AB.

Q7. The relative tendency of an atom in a molecule to attract the shared pair of electrons towards itself is termed as its
Answer : Option D
Explaination / Solution:

A qualitative measure of the ability of an atom in a chemical compound to attract shared electrons to itself is called electronegativity. Unlike ionization enthalpy and electron gain enthalpy, it is not a measureable quantity. However, a number of numerical scales of electronegativity of elements viz., Pauling scale, Mulliken-Jaffe scale, Allred-Rochow scale have been developed. The electronegativity of any given element is not constant; it varies depending on the element to which it is bound.

Q8. Holes in the ozone layer are thought to have been caused by:
Answer : Option A
Explaination / Solution:

CFC’s causes hole in the ozone layer.

Q9.

Give the number of electrons in the species,  and .


Answer : Option C
Explaination / Solution:

atomic number O has atomic number = 8 so number of electrons in = 16

while in  there is one unit positive charge so no. of electron =15.


Q10. Ag+ ion is isoelectronic with
Answer : Option B
Explaination / Solution:

Ag+ is isoelectronic with Cd2+