Chemistry · Science General

Periodic Table and Elements

406 Questions

The periodic table and elements questions test knowledge of chemical properties, atomic structures, and periodic trends. Topics include alkali metals, transition elements, and ionisation potential. These concepts frequently appear in general science sections of competitive examinations.

Alkali metals propertiesTransition elementsLattice energyIonisation potentialAlkaline earth metals

Periodic Table and Elements Questions

Multiple choice

The existence of which of the following became the reason for the failure of Mendeleev's periodic law?

  1. Alkali metals

  2. Alkaline earth metals

  3. Halogens

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

Since Mendeleev’s periodic law was based on atomic masses of the elements, the isotopes should have been  placed in different slots despite the fact that they represent the same element. This was one of the major disadvantage of Mendeleev’s periodic law.

Multiple choice

Characteristic property of alkali metals is

  1. they are good reducing agents

  2. they are good oxidising agent

  3. electropositive character decreases down the group

  4. high ionisation potential
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Due to low ionisation potential they readily give electrons for reduction. Hence they act as reducing agents