Chemistry · Science General

Periodic Table and Elements

421 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

Lithium and sodium are placed in the same group of Mendeleev's periodic table. Which of the following statements is true with regard to lithium and sodium?

(i) They have the same electronic configuration. (ii) The formula of their hydrides is the same. (iii) The formula of their oxides is the same.

  1. (i) and (ii)

  2. (ii)

  3. (iii)

  4. (ii) and (iii)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Lithium and sodium are placed in the same group of Mendeleev's periodic table because they have the same formulas of hydrides (like LiH and NaH) and oxides (like Li2O and Na2O).

Multiple choice

Which of the following elements will have the lowest electronegativity?

  1. Bromine

  2. Chlorine

  3. Fluorine

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

The given elements belong to group 17 of the periodic table. As we move from top to bottom in a period in the periodic table, the electronegativity decreases because of increase in atomic size. Hence, from all the given elements, iodine will have the lowest electronegativity. 

Multiple choice

Which one of the following statements is not valid for all noble gases?

  1. They have general electronic configuration ns2np6.

  2. They are monatomic gases.

  3. They have positive electron gain enthalpy.

  4. They are colourless, odourless and tasteless.

  5. They belong to group 18 of the periodic table.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

All noble gases have general electronic configuration ns2np6, except helium which has 1s2.

Multiple choice

Which among the following has the largest atomic size?

  1. Rb

  2. K

  3. Cs

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

Atomic radius is generally stated as being the total distance from an atom’s nucleus to the outermost orbital of electron. In simpler terms, it can be defined as something similar to the radius of a circle, where the center of the circle is the nucleus and the outer edge of the circle is the outermost orbital of electron. As you begin to move across or down the periodic table, trends emerge that help explain how atomic radii change. So, we see that Cs has the largest atomic size.

Multiple choice

According to Newlands, sodium and lithium are placed in the same column. Which option gives the correct reason?

  1. They have similar properties.

  2. They have the same atomic mass.

  3. They belong to the same triad.

  4. Both had same size.

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Newlands found that every eighth element has similar physical and chemical properties. If one starts with lithium (atomic mass = 6) and arrange the elements in increasing order of their atomic masses, the eighth element will be sodium (atomic mass = 23). Both elements show the same physical and chemical properties.

Multiple choice

Which of the following is a correct statement?

  1. 5f orbital electrons are more shielded than 4f orbital electrons.

  2. Zr and Hf have almost the same atomic radius.

  3. Uranium belongs to lanthanide series.

  4. Lanthanides are silvery white metals because of d-d transition.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Zr and Hf have almost the same atomic radius because of lanthanide contraction.

Multiple choice

Which of the following statements is incorrect?

  1. +2 and +3 oxidation states are more common for the elements in 3d series.

  2. Atomic sizes of elements in 4d series are much smaller than those of the corresponding members in 5d series.

  3. The melting and boiling points of the elements in 3d series are lower than those of corresponding members in the 4d and 5d series.

  4. The enthalpies of atomisation of the elements in 3d series are lower than those of corresponding members in the 4d and 5d series.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Atomic sizes of elements in 4d series are virtually the same as those of the corresponding members in the 5d series. This is because of lanthanide contraction.

Multiple choice

Which of the following statements are not true?

  1. Compounds of alkaline earth metals are less hydrated than those of alkali metals.
  2. Quicklime exhibits thermoluminescence.
  3. Aqueous solution of calcium hydroxide is known as milk of lime.
  4. Oxide and hydroxide of beryllium are amphoteric in nature.

  1. 1 and 2

  2. 1 and 3

  3. 1 and 4

  4. 2 and 3

  5. 3 and 4
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Compounds of alkaline earth metals are more extensively hydrated than those of alkali metals.

Multiple choice

Which of the following statements are true regarding transition elements?

  1. Osmium is the densest transition metal.
  2. All the elements of 3d series are good reducing agents.
  3. Highest oxidation state shown by any transition element is + 7.
  4. The reactivity of transition elements decreases with the increase in their atomic number.

  1. 1 and 2

  2. 1 and 3

  3. 2 and 3

  4. 2 and 4

  5. 3 and 4
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

All the elements of 3d series are good reducing agents except copper. Highest oxidation state shown by any transition element is +8 (Ru in 4d series and Os in 5d series).

Multiple choice

Which of the following terms statements are correct?

  1. All alkali metal elements form solid hydrogen carbonates.
  2. Calcium is fifth most abundant element in the earth’s crust.
  3. Francium is highly radioactive.
  4. Hydration enthalpies of alkaline earth metal ions are larger than those of alkali metal ions.

  1. 1 and 2

  2. 1 and 4

  3. 2 and 3

  4. 2 and 4

  5. 3 and 4
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Francium is highly radioactive; its longest-lived isotope 223-Fr has a half-life of only 21 minutes. The hydration enthalpies of alkaline earth metal ions are larger than those of alkali metal ions. Thus, compounds of alkaline earth metals are more extensively hydrated than those of alkali metals, e.g. MgCl2 and CaCl2 exist as MgCl2.6H2O and CaCl2• 6H2O while NaCl and KCl do not form such hydrates.