Chemistry

Periodic Classification and Elements

1,176 Questions

Periodic classification organizes chemical elements based on atomic structure, periodic laws, and elemental properties. It covers historical classification systems, electron configurations, and periodic trends. Test takers preparing for chemistry sections will find these questions crucial for mastering fundamental element properties and atomic interactions.

Periodic table structureAtomic orbitalsElement identificationPeriodic laws

Periodic Classification and Elements Questions

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

Group $16$ element are called:

  1. Carbon family

  2. Chalcogen family

  3. Halogen family

  4. Nitrogen family
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The chalcogens are the chemical elements in the group $16$ of the periodic table. 

This group is also known as the oxygen family. It consists of the elements oxygen, sulfur, selenium, tellurium, and the radioactive element polonium. 

Hence, the correct answer is option $B$.
Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

The element with highest boiling point in the following is :

  1. Oxygen

  2. Sulphur

  3. Tellurium

  4. Polonium
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Boiling point is a physical property so depends on van der waal forces of attraction and van der waal forces $\propto$ molecular mass $\propto$ High boiling point
$\therefore $ Boiling point order :- $Te > Se > S > O$

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

Which of the following is a true Chalcogen:

  1. Nitrogen

  2. Oxygen

  3. Polonium

  4. Chlorine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation


Chalcogen is VI group (Oxygen family)
having elements:-
                 O
                  S
                  Se
                   Te
                    Po

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

Only one element of _______form hydride.

  1. group 6

  2. group 7

  3. group 8

  4. group 9
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Only one element of chromium from group $6$,that is $CrH$.

So,the answer is only one element of group $6$ forms hydrites.
These type of hybrides are classified into metalic or non-stoichiometric type of hydrides.

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

Identify the group 16 $(VI\space A)$ elements which is the most electronegative ?

  1. $ O $
  2. $ S $
  3. $ Te$
  4. $ Po $
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

All theses O,S,Se,Te,Po are group 16 elements from top to bottom.As we move from top to bottom in a group as the size increses the electronegativity  decreases.So most electronegative element is Oxygen
The order of electronegativity is O>S >Se>Te.Po.
Hence option A is correct.

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

Name of the group-16 element which shows maximum catenation.

  1. Oxygen

  2. Sulphur

  3. Selenium

  4. Tellurium
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The greater the element-element bond strength, the higher is the tendency towards catenation. 

As the size increases from S to Te, the bond dissociation energy decreases. O - O bond energy is, however, smaller than that of S-S because of inter electronic repulsions within the smaller size of oxygen atoms. 

Thus, sulphur has a maximum tendency towards catenation.

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

In 16 group element, sulphur, selenium and tellurium are respectively :

  1. Insulator, Semiconductors and Semiconductor.

  2. Semiconductors , Insulator and Insulator.

  3. Insulator, Insulator and Semiconductor.

  4. Semiconductors, Insulator and Semiconductor.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
 Sulphur is non metal.It has the properties of poor conductor of both heat and electricity.It is weak,dull and can be easily breakable.

As we  move from top to bottom in  group the conductivity of elements increases so the sulfur, selenium  and tellurium are Insulator, Semiconductors and Semiconductors respectively.

Hence option A is correct.
Multiple choice evs let's play with water law of constant proportion - i law of constant proportion law of definite proportions

When elements react, their atoms combine in :

  1. a simple whole number ratio (unique for each pair of elements)

  2. arbitrary proportions

  3. simple whole number ratios (more than one possible)

  4. 1:1 ratios
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The law of multiple proportions state that if two elements form more than one compound between them then the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers.

Multiple choice photosystems photosynthesis in plants metabolism, cell respiration, and photosynthesis photosynthesis in higher plants biology

In PS I, the carrier that picks up electrons from $P _{700}$ is

  1. Fe protein

  2. Fe-S protein

  3. Fe-Cu protein

  4. Fe-Mg protein
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A photosystem is composed of chlorophyll 'a' molecule which can absorb the wavelength of 700 nm. The chlorophyll a molecule acts as a reaction centre. PS-I is involved in a non-cyclic type of photophosphorylation where there is a chain of electron carriers and acceptors that transmits the electron from one to another. The primary electron acceptor is the ferredoxin molecule which is composed of Fe-S protein

So, the correct option is Fe-S protein'

Multiple choice photosystems photosynthesis in plants metabolism, cell respiration, and photosynthesis photosynthesis in higher plants biology

PS II accepts electrons from

  1. $OH^-$
  2. $O^{2-}$
  3. $H^+$

  4. Both A and C
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Water is split in chloroplasts in the light reaction of photosynthesis. Chlorophyll, acting as a photopigment, captures sunlight and transfers that energy to an electron pair of a water molecule. Water molecule is separated into 2 protons, molecular oxygen and a free electron pair, which then enters to PS II and accepted by plastoquinone and carried by variety of electron acceptors in a series of redox potential. The excited electrons are used for photolysis of water generating oxygen and protons which then used in synthesis of ATP and NADPH.

Multiple choice physics semiconductors band theory of solids, a brief introduction electron energies in solids energy bands

Carbon, silicon and germanium have four valence electrons each. These are characterised by valence and conduction bands separated by energy band gap respectively equal to $(E _g) _C,\, (E _g) _{Si}$ and $(E _g) _{Ge}$.Which of the following statements is true?

  1. $(E _g) _{Si}\, <\, (E _g) _{Ge}\, <\, (E _g) _C$
  2. $(E _g) _{C}\, <\, (E _g) _{Ge}\, >\, (E _g) _{Si}$
  3. $(E _g) _{C}\, >\, (E _g) _{Si}\, >\, (E _g) _{Ge}$
  4. $(E _g) _{C}\, =\, (E _g) _{Si}\, =\, (E _g) _{Ge}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
For given elements, the energy band gap of carbon is the maximum and of germanium is the least.
Hence option C is correct.