Chemistry

Periodic Classification and Elements

1,092 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

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

All the elements in oxygen family are:

  1. Non-metal

  2. Mettaloids

  3. Radioactive

  4. Polymorphic
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

All the elements in oxygen family are polymorphic (Polymorphism is the ability a material to exist in two or more forms or crystalline structures of the same chemical compound or element).
Hence option D 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 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.
Multiple choice physics semiconductors band theory of solids, a brief introduction electron energies in solids energy bands

The highest occupied energy band is called ________ and lowest unoccupied energy band is called the _________ .

  1. Band Gap, Conduction band

  2. Valence band, Band Gap

  3. Conduction band, Valence band

  4. Valence band, Conduction band
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The highest energy band occupied by electrons is the valence band. In a conductor, the valence band is partially filled, and since there are numerous empty levels, the electrons are free to move under the influence of an electric field; thus, in a metal the valence band is also the conduction band. The valence band is the highest range of electron energies in which electrons are normally present at absolute zero temperature, while the conduction band is the lowest range of vacant electronic states. This distinction is meaningless in metals as the highest band is partially filled, taking on the properties of both the valence and conduction bands.

Multiple choice biology natural disasters: winds, storms and cyclones composition of air introduction to air natural resources - air

Noble gases have the _________ among the elements of each period.

  1. Largest ionization potential

  2. Lowest ionization potential

  3. Greatest melting point

  4. Low electronic configuration
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Noble gases have the largest ionization potential among the elements of each period, which reflects the stability of their electron configuration and is related to their relative lack of chemical reactivity.