Periodic Table of Elements

The melting point of iodine is higher than that of chlorine. Which one of the following statements best explains this phenomenon?

• Iodine is darker in colour than chlorine

• Iodine atoms are smaller than chlorine atoms

• Iodine atom has more electrons than a chlorine atom

• The intermolecular forces in iodine is stronger than in chlorine

Which element is most likely to be an effective catalyst in the catalytic converter of car exhausts?

• Lithium

• Aluminium

• Magnesium

• Platinum

An atom of element X has 4 shells containing electrons. When element X reacts with chlorine, a compound with formula XCl is formed. Which of the following is the element X?

• Calcium

• Potassium

• Sodium

• Silicone

Table shows the arrangement of electrons of elements in Period 3 of the Periodic Table. Which one of the following shows the correct descending order of their atomic radii?

• M,L,N,P,K

• L,M,N,K,P

• P,K,N,M,L

• K,L,M,N,P

The following are the uses of inert gases except

• used in advertising lights

• used to fill a weather balloons

• used in lasers for eye treament

• used as a catalyst in Haber process

Sodium and rubidium are both elements in Group 1 of the Periodic Table. Which of the following statements is correct?

• Both metals form acidic oxides

• Rubidium has a lower melting point than sodium

• Rubidium reacts less quickly with water than sodium

• Rubidium has less electrons compared to sodium

In what ways Mendeleev's classification system was a great improvement over John Newlands table?

• I and IV only

• II and IV only

• I and III only

• I, II and III only

The different reactivity of Group 1 elements of the Periodic Table is due to the

• I,II,III only

• I,II,IV only

• I,III,IV only

• II,III,IV only

Which one of the following statements best accounts for the inert properties of Group 18 elements?

• All of them have 18 elements in an atom

• All of them have 8 valence electrons in each atom

• All of them are rare gases and very difficult to find

• Their valence shell are completely filled by electrons

Fluorine is the first element in Group 17 of the Periodic Table. Which statement about fluorine is not correct?

• It forms ionic compound with sodium

• It is gas at room temperature and pressure

• Its molecules are diatomic at room temperature

• Its molecules are monoatomic at room temperature