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

Which of the following elements is the most reactive alkali metal?

  1. Lithium

  2. Sodium

  3. Potassium

  4. Rubidium

  5. Cesium
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Cesium is the most reactive alkali metal due to its low ionization energy and large atomic radius, making it highly susceptible to losing an electron and forming positive ions.

Multiple choice

Which of the following is NOT a characteristic property of alkali metals?

  1. Low melting point

  2. High boiling point

  3. Shiny appearance

  4. Good electrical conductivity

  5. High reactivity
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Alkali metals generally have low boiling points due to weak interatomic forces. High boiling point is not a characteristic property of alkali metals.

Multiple choice

Which of the following Group 2 elements has the highest ionization energy?

  1. Beryllium

  2. Magnesium

  3. Calcium

  4. Strontium

  5. Barium
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Beryllium has the highest ionization energy among Group 2 elements due to its small atomic radius and high nuclear charge. It requires more energy to remove an electron from a beryllium atom compared to other Group 2 elements.

Multiple choice

Which of the following Group 1 elements is liquid at room temperature?

  1. Lithium

  2. Sodium

  3. Potassium

  4. Rubidium

  5. Cesium
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Cesium is the only Group 1 element that is liquid at room temperature. It has a low melting point of 28.5 °C and a low boiling point of 678 °C.

Multiple choice

Which of the following elements has the largest atomic radius?

  1. Li

  2. Na

  3. K

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

Atomic radius generally increases down a group and decreases across a period. Rb is in the same group as Li, Na, and K, and it is the lowest in the group, so it has the largest atomic radius.

Multiple choice

Which of the following elements has the highest ionization energy?

  1. F

  2. Cl

  3. Br

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

Ionization energy generally increases across a period and decreases down a group. F is in the same period as Cl, Br, and I, and it is the furthest to the right in the period, so it has the highest ionization energy.

Multiple choice

Which of the following elements has the most negative electron affinity?

  1. O

  2. S

  3. Se

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

Electron affinity generally becomes more negative across a period and less negative down a group. O is in the same period as S, Se, and Te, and it is the furthest to the right in the period, so it has the most negative electron affinity.

Multiple choice

Which of the following elements is the most electronegative?

  1. F

  2. Cl

  3. Br

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

Electronegativity generally increases across a period and decreases down a group. F is in the same period as Cl, Br, and I, and it is the furthest to the right in the period, so it is the most electronegative.

Multiple choice

Which of the following elements is the most metallic?

  1. Li

  2. Na

  3. K

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

Metallic character generally increases down a group and decreases across a period. Rb is in the same group as Li, Na, and K, and it is the lowest in the group, so it is the most metallic.

Multiple choice

Which of the following elements has the lowest melting point?

  1. He

  2. Ne

  3. Ar

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

Melting point generally decreases down a group and increases across a period. He is in the same period as Ne, Ar, and Kr, and it is the furthest to the left in the period, so it has the lowest melting point.

Multiple choice

Which of the following elements is the most dense?

  1. Os

  2. Ir

  3. Pt

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

Density generally increases down a group and across a period. Os is in the same period as Ir, Pt, and Au, and it is the furthest to the left in the period, so it is the most dense.

Multiple choice

Which of the following elements is the least dense?

  1. Li

  2. Na

  3. K

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

Density generally increases down a group and across a period. Li is in the same group as Na, K, and Rb, and it is the highest in the group, so it is the least dense.

Multiple choice

Which of the following elements is the most reactive?

  1. Li

  2. Na

  3. K

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

Reactivity generally increases down a group and decreases across a period. Li is in the same group as Na, K, and Rb, and it is the highest in the group, so it is the most reactive.

Multiple choice

Which of the following elements is the least reactive?

  1. He

  2. Ne

  3. Ar

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

Reactivity generally increases down a group and decreases across a period. He is in the same period as Ne, Ar, and Kr, and it is the furthest to the left in the period, so it is the least reactive.

Multiple choice

Which of the following elements is the most likely to form a cation?

  1. Li

  2. Na

  3. K

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

Elements in the leftmost column of the periodic table are most likely to form cations. Li is in the leftmost column, so it is the most likely to form a cation.