Question 1

Which characteristic sets the Group 1 metals apart from other metallic elements?&#10;A) They are very soft.&#10;B) They have low metallic lustre.&#10;C) They are poor conductors of electricity.

Accepted Answer

Group 1 metals, also known as alkali metals, are very soft and can often be cut with a knife, which sets them apart from most other metallic elements that tend to be harder.

Question 2

Calcium metal is required for isolation of:&#10;A) Li&#10;B) K&#10;C) Rb

Accepted Answer

C

Question 3

Find the correct statement(s):&#10;(i) All Group 1 elements form halides by direct combination of the elements.&#10;(ii) The only structural type for the Group 1 halides is NaCl structure type.&#10;(iii) Based on the general trends, it is expected that LiF is going to have the most stable lattice while CsI the least stable lattice.&#10;A) (i) and (ii)&#10;B) (i) and (iii)&#10;C) (ii) and (iii)

Accepted Answer

(i) is correct because all Group 1 elements (alkali metals) readily react with halogens to form halides through direct combination. (iii) is correct because the lattice energy, which contributes to the stability of the ionic lattice, depends on the charge density of the ions. LiF has the smallest ions with the highest charge density, leading to the most stable lattice, while CsI has the largest ions with the lowest charge density, leading to the least stable lattice. (ii) is incorrect because Group 1 halides can adopt different structure types depending on the size of the cation and anion, not just the NaCl structure type.

Question 4

Identify rubidium superoxide: A) RbO₂ B) RbO₃ C) Rb₉O₂

Accepted Answer

Rubidium superoxide is RbO₂, where rubidium forms a compound with the superoxide ion (O₂^-).

Question 5

Identify the correct product(s) formed in the reaction between Na₂O and water. A) NaOH B) NaOH and H₂O₂ C) NaOH, H₂O₂ and O₂

Accepted Answer

When Na₂O reacts with water, it forms NaOH and H₂O₂. However, the correct product for this specific reaction is NaOH, as the reaction primarily yields sodium hydroxide.

Question 6

Which statement(s) is(are) correct about the Group 1 carbonates?
(i) All Group 1 carbonates have low solubility in water.
(ii) Thermal decomposition of the Group 1 carbonates produces hydrogencarbonates.
(iii) Sodium and potassium carbonates are important raw materials in glass industry.

A) (i) and (iii)
B) (iii) only
C) (ii) and (iii)

Accepted Answer

Group 1 carbonates generally increase in solubility as you move down the group, making statement (i) incorrect. Thermal decomposition of Group 1 carbonates typically produces the metal oxide and carbon dioxide, not hydrogencarbonates, making statement (ii) incorrect. Statement (iii) is correct as sodium and potassium carbonates are indeed important raw materials in the glass industry.

Question 7

Thinking about the nitrides and carbides of the Group 1 elements, in what way does lithium differ from other elements of this group?&#10;A) Only Li reacts directly with nitrogen and carbon to produce a nitride and a carbide respectively&#10;B) Lithium nitride and carbide are basic, others are neutral.&#10;C) Lithium nitride and carbide are soluble, the others are not.

Accepted Answer

Lithium is unique among Group 1 elements because it can directly react with nitrogen and carbon to form a nitride and a carbide, respectively, due to its small size and high polarizing power. Other Group 1 elements do not directly form these compounds under normal conditions.

Question 8

Which compound is produced upon the decomposition of the metal-ammonia solution?&#10;A) a nitride&#10;B) an amide&#10;C) an azide

Accepted Answer

Upon the decomposition of metal-ammonia solutions, an amide is produced. This occurs because the metal reacts with the ammonia (NH3) to form a metal amide (MNH2), where M represents the metal.

Question 9

Which of the following donor atoms is unlikely to be coordinated to a Group 1 cation?&#10;A) O&#10;B) N&#10;C) P

Accepted Answer

Group 1 cations, being highly electropositive, tend to form ionic bonds rather than coordinate bonds. However, when they do form complexes, the donor atoms are typically those with lone pairs that are less localized and thus more easily donated to the metal ion. Oxygen (O) and nitrogen (N) atoms, being small with lone pairs that are relatively available for donation, can coordinate to Group 1 cations. Phosphorus (P), on the other hand, has its lone pairs more delocalized due to its larger size and lower electronegativity, making it less likely to act as a donor atom to Group 1 cations in coordination complexes.

Question 10

Find the correct statement:&#10;A) The Group 1 organometallic compounds are very reactive towards polar compounds.&#10;B) The Group 1 organometallic compounds are covalent.&#10;C) Most of the Group 1 organometallic compounds are liquids or gases.

Accepted Answer

Group 1 organometallic compounds are indeed very reactive towards polar compounds due to the high reactivity of Group 1 metals. These metals easily lose an electron to form highly reactive cations that can interact with polar compounds.

Deck 11: The Group 1 Elements