List of top Chemistry Questions on Periodic Table

Bauxite is the principal ore used in the commercial extraction of aluminium. The Bayer’s process is used to refine bauxite into pure alumina, with caustic soda playing a crucial role in the initial stage of the process. Based on this, answer the following questions: 

(a) Explain the reason behind the addition of caustic soda during the Bayer’s process. 
(b) Write a balanced chemical equation representing the reaction between bauxite and caustic soda during the Bayer’s process. 
 

Carbon reacts with an acid to form carbon dioxide, water and nitrogen dioxide.
(a) Name the acid used in the reaction.
(b) Write a balanced chemical equation for the reaction that occurs.

Anil is a laboratory assistant in a college. He prepared nitric acid but stored it in a transparent container exposed to sunlight. After a few days, brown fumes were observed in the container and the acid turned slightly yellowish in colour. 

(a) What was the error made by Anil while storing the acid? 
(b) Why were brown fumes observed in the container? 
(c) How can the yellowish tinge in the acid be removed? 
 

State whether the following statements are True or False. 

(a) Organic compounds having different molecular formula, but same structural formula are called isomers. 
(b) A salt is a compound formed by partial or complete replacement of the hydrogen ion of an acid by a metal or electropositive ion. 
 

Element A belongs to group 15 and period 2 of the Periodic Table.
(a) Identify the element A.
(b) Write the formula of the compound formed when element A combines with hydrogen.
(c) Draw the dot (●) and cross (×) structure of the compound formed in (b) above.
An atom of X forms an ion according to the equation ( X + 2e^- X^2- ). The atomic number of the atom X is:
The electronic configuration of an element is 2,8,2. The hydroxide of this element can produce ______ hydroxyl ions per molecule.

Which of the following element pairs will form an ionic bond? 

 

In period 4 of the periodic table, the elements with highest and lowest atomic radii respectively are:


The correct sequence of reagents for the above conversion of X to Y is :

Which of the following represents the correct trend for the mentioned property?
A. F $>$ P $>$ S $>$ B \quad -- First Ionization Energy
B. Cl $>$ F $>$ S $>$ P \quad -- Electron Affinity
C. K $>$ Al $>$ Mg $>$ B \quad -- Metallic character
D. K₂O $>$ Na₂O $>$ MgO $>$ Al₂O₃ \quad -- Basic character
Choose the correct answer from the options given below:
Statement-I : $\text{K}>\text{Mg}>\text{Al}>\text{B}$ metallic character order. Statement-II: Ionic radius of any element is less than its atomic radius.
Which of the following electronegativity order is incorrect?

Which of the following Statements are NOT true about the periodic table? 
A. The properties of elements are a function of atomic weights. 
B. The properties of elements are a function of atomic numbers. 
C. Elements having similar outer electronic configuration are arranged in the same period. 
D. An element's location reflects the quantum numbers of the last filled orbital. 
E. The number of elements in a period is the same as the number of atomic orbitals available in the energy level that is being filled.

Heat treatment of muscular pain involves radiation of wavelength of about 900 nm. Which spectral line of H atom is suitable for this? Given: Rydberg constant \( R_H = 10^5 \, \text{cm}^{-1} \), \( h = 6.6 \times 10^{-34} \, \text{J s} \), and \( c = 3 \times 10^8 \, \text{m/s} \)
The property/properties that show irregularity in the first four elements of group-17 are:

Match the LIST-I with LIST-II.

LIST-ILIST-II
A.Pnicogen (group 15)I.Ts
B.Chalcogen (group 16)II.Og
C.Halogen (group 17)III.Lv
D.Noble gas (group 18)IV.Mc

Choose the correct answer from the options given below :

Which of the following statements are correct? 
A. The process of the addition an electron to a neutral gaseous atom is always exothermic 
B. The process of removing an electron from an isolated gaseous atom is always endothermic 
C. The 1st ionization energy of the boron is less than that of the beryllium 
D. The electronegativity of C is 2.5 in $ CH_4 $ and $ CCl_4 $ 
E. Li is the most electropositive among elements of group 1 
Choose the correct answer from the options given below

Atomic number of element with lowest first ionisation enthalpy is:
Which of the following has the highest atomic number?
The element that does not belong to the same period of the remaining elements (modern periodic table) is:
Radius of the first excited state of Helium ion is given as:
\(a_0\) = radius of first stationary state of hydrogen atom.

Match List-I with List-II:

Given below are two statements: Statement (I): According to the Law of Octaves, the elements were arranged in the increasing order of their atomic number.
Statement (II): Meyer observed a periodically repeated pattern upon plotting physical properties of certain elements against their respective atomic numbers. In the light of the above statements, choose the correct answer from the options given below:
Which among the following electronic configurations belong to main group elements?
A. [Ne]3s$^1$
B. [Ar]3d$^3$4s$^2$
C. [Kr]4d$^5$3s$^2$5p$^5$
D. [Ar]3d$^10$4s$^1$
E. [Rn]5f$^7$6d$^2$7s$^2$
Choose the correct answer from the options given below: