Which of the following best describes the structure of metals?

A. Lattice of positive ions surrounded by a sea of delocalised electrons

B. Covalently bonded network of atoms

C. Ionic lattice structure with alternating positive and negative ions

D. Discrete molecules held together by van der Waals forces

Why do metals generally have high electrical conductivity?

A. They have mobile ions

B. They have a full valence shell

C. They have delocalised electrons that can move freely

D. They have strong covalent bonds

Which property is NOT typically associated with metals?

A. Brittleness

B. Malleability

C. Ductility

D. High melting point

Why are alloys often used instead of pure metals?

A. Alloys are cheaper

B. Alloys have enhanced properties like strength or resistance to corrosion

C. Alloys are more abundant

D. Alloys are less dense

Which of the following is an example of an alloy?

A. Oxygen

B. Sodium chloride

C. Steel

D. Water

a) Describe the concept of a "sea of delocalised electrons" in the context of metallic bonding. [3]

b) How does this "sea of delocalised electrons" contribute to the electrical conductivity of metals? [2]

a) Explain the terms malleability and ductility as they relate to metals. [2]

b) How does the nature of metallic bonding contribute to the malleability and ductility of metals? [3]

a) Why is there a need to make and use alloys like iron and steel in society? [3]

b) How does the addition of other elements to create an alloy affect the properties of the base metal? [2]

a) Describe the significance of the "sea of delocalised electrons" in explaining the high thermal conductivity of metals. [3]

b) Why do metals generally have high melting and boiling points? [2]

c) Explain why mercury, a metal, is liquid at room temperature. [2]

a) What are van der Waals forces, and how do they relate to non-polar molecules? [3]

b) List two factors that affect the strength of van der Waals forces. [2]

c) Why do larger non-polar molecules generally have higher boiling points than smaller non-polar molecules? [2]

What is the primary reason for the malleability of metals?

A. Presence of covalent bonds

B. Presence of ionic bonds

C. Ability of metal cations to slide past each other without breaking the metallic bond

D. High electronegativity of metal atoms

Which metal is typically alloyed with iron to produce stainless steel?

A. Copper

B. Aluminium

C. Chromium

D. Zinc

What is the primary role of the delocalised electrons in metallic bonding?

A. To form ionic bonds

B. To neutralise the metal cations

C. To facilitate chemical reactions

D. To hold the metal cations together in a lattice

Which of the following is NOT a property enhanced by the formation of alloys?

A. Electrical conductivity

B. Reactivity

C. Strength

D. Resistance to corrosion

Why do metals like iron need to be alloyed to be used in construction?

A. To make them less dense

B. To increase their melting point

C. To make them more malleable

D. To increase their strength and durability

a) What is a hydrogen bond, and how does it differ from a regular dipole-dipole interaction? [3]

b) List two factors necessary for the formation of hydrogen bonds. [2]

c) Explain the significance of hydrogen bonding in the structure of DNA. [3]

a) Explain the term "alloy" and its significance in enhancing the properties of metals. [3]

b) Describe the difference between a substitutional alloy and an interstitial alloy. [2]

c) Why is steel, an alloy of iron, often preferred over pure iron for construction purposes? [3]

a) Describe the concept of a "sea of delocalised electrons" in metals. [2]

b) How does this "sea" contribute to the electrical conductivity of metals? [3]

c) Explain the terms malleability and ductility in the context of metallic bonding. [3]

d) Why might an alloy be less malleable than its constituent pure metal? [2]

a) What is an alloy? [2]

b) Explain why alloys are often harder than pure metals. [3]

c) Describe the significance of alloys in modern society, especially in relation to iron and steel. [3]

d) Why might a metal alloy be more resistant to corrosion than its pure metal counterpart? [2]

a) What is the primary reason metals are good conductors of heat? [2]

b) How does the structure of metallic bonding contribute to the high melting and boiling points of metals? [3]

c) Why are metals typically shiny or lustrous in appearance? [2]

d) Explain the importance of creating alloys when a specific set of properties is required for an application. Provide an example. [3]