Which of the following relations is correct? The radius of …………

• X⁺ ion > that of X^- ion.

• X^- ion > that of X atom

• X⁺ ion > that of X^- ion.

• X⁺ ion > that of X atom

Which of the following best describes a period in the Periodic Table?

• A collection of elements in a single column

• A collection of elements in a single diagonal

• All elements with a specific number of neutrons in their nuclei

• All nonmetals

• A collection of elements in a single row

If the length of the bond in A₂ molecule equals 1.98 A°, and its length in AB molecule equals 1.29A°, what is the bond length in B₂ molecule?

• 0.69 A°

• 3.27 A°

• 1.32 A°

• 0.6 A°

Which of the following choices is more accurate in representing the ratio of the atomic radius of sodium to its ionic radius (both estimated in picometer)?

• 138/235

• 190/102

• 144/143

As the atomic radius …………… in the alkali metal group, the attraction force between the nucleus and the valence electrons …………… and it becomes easy to lose it.

• increases, decreases

• increases, remains the same

• decreases, decreases

• increases, increases

Which of the following equations correctly shows the first electron affinity of an atom?

• X^-(g) → X(g) + e^-

• X^-(g) + e^- → X(g)

• X(g) + X(g) → X⁺(g) + X^-(g)

• X(g) → X⁺(g) + e^-

• X(g) + e^- → X^-(g)

Which of the following information Berzelius might relied on in his classification of the elements? ………

• Atomic number of the elements.

• Electronic configuration of the elements.

• Degree of electricity and heat conductivity.

• The quantum numbers of the last electron in each element

Arsenic ₃₃As and antimony ₅₁Sb are similar in ………

• both being from the fourth period elements.

• both being from group (5A).

• their electric conductivity being higher than that of metals.

• the four quantum numbers of the last electron in the atom of each of them.

What products are formed when sodium oxide reacts with hydrochloric acid?

• NaCl, H₂, and O₂

• NaCl and H₂O

• Na and HClO

• Na, O₂, H₂, and Cl₂

A metal oxide and an acid reacted together to form zinc chloride and water. What were the metal oxide and the acid?

• Zinc oxide and hydrochloric acid

• Zinc oxide and sulfuric acid

• Zinc metal and nitric acid

• Zinc metal and hydrochloric acid

• Zinc chloride and zinc oxide