Triple Chemistry C - Quiz

A polymer contains two types of bond. What are they?

When metals form ions, they [blank_start]lose[blank_end] electrons, resulting in a [blank_start]positively[blank_end] charged atom (otherwise known as a cation). When a non-metal forms an ion, they [blank_start]receive[blank_end] electrons, resulting in a [blank_start]negatively[blank_end] charged ion (also known as an anion). The amount of electrons gained or lost forms the [blank_start]charge[blank_end] of an ion. The [blank_start]transferring[blank_end] of electrons in ionic bonding can be shown with a [blank_start]dot[blank_end] and cross diagram.

As you go down the groups, the reactivity changes. In groups 1 and 2, as you go down, the reactivity [blank_start]increases[blank_end]. This is because the outer shell is [blank_start]further away[blank_end] from the [blank_start]nucleus[blank_end] and the electrons have [blank_start]less[blank_end] of an attraction to the nucleus, meaning they can give away their valence electrons easier. As you go down groups 6 and 7, it is the [blank_start]opposite[blank_end]. As you go down the elements become [blank_start]less[blank_end] reactive. The valence electrons are still less attracted to the nucleus, but that makes it [blank_start]harder[blank_end] for them to attract more electrons.

Ionic compounds have a giant [blank_start]regular[blank_end] [blank_start]lattice[blank_end] [blank_start]structure[blank_end]. The positive / negative bonds hold each [blank_start]ion[blank_end] in place in the [blank_start]3D[blank_end] structure.

The order of strength in bonds from highest to lowest is: Ionic Metallic Covalent Intermolecular.

Ionic compounds conduct electricity as solids, liquids and dissolved.

Metals also have a [blank_start]lattice[blank_end] structure. The valence electrons of each metal atom are lost to the structure to create a sea of [blank_start]delocalised[blank_end] electrons. This turns each metal atom into a positive [blank_start]ion[blank_end]. The positive / negative charges create an electrostatic forces that keep the delocalised electrons within the structure, but still free to move around. Pure metals have a [blank_start]high[blank_end] melting and boiling point, high tensile strength and are also malleable.

Tick all that apply about small molecules.

Giant covalent structures are sometimes known as macromolecules.

An alletrope is a pure element in a [blank_start]different[blank_end] physical form. There are many alletropes of carbon. Diamond is one of them. It has a [blank_start]tetrahedral[blank_end] structure where each carbon atom forms [blank_start]four[blank_end] covalent bonds. This makes it very [blank_start]hard[blank_end] and a non-conductor. Diamond is [blank_start]lustrous[blank_end] and is good for [blank_start]jewellery[blank_end]. Graphite (and graphene, which is just [blank_start]a single layer[blank_end] of graphite) is different. It has a hexagonal ring structure that forms [blank_start]3[blank_end] covalent bonds. This leaves one free electron per carbon atom, making graphite and graphene very good conductors of electricty and a very good insulator. The layers of graphene in graphite are held together very [blank_start]loosely[blank_end], which means the layers can slide over each other easily. Graphite is [blank_start]black[blank_end] and opaque with a high melting point, whereas graphene is just [blank_start]one atom[blank_end] thick, transparent and light. Graphite and graphene are used in pencils and graphene is often used in computer microchips.

Nanoparticles are between [blank_start]1[blank_end] and 100 nanometres. They are [blank_start]bigger[blank_end] than atoms and small molecules but [blank_start]smaller[blank_end] than pretty much everything else. They have a high surface area to [blank_start]volume[blank_end] ratio meaning a bigger portion of the particle can react on contact. Nanoparticles are good [blank_start]catalysts[blank_end] (meaning they can speed up a reaction)< they are good in cosmetics and lubricants, they conduct electricity, are very durable and can contain anti-bacterial proerties. A [blank_start]fullerene[blank_end], which can deliver drugs to the body, is a good example of a nanoparticle. Unfortunately, the effect of nanoparticles on the human body is not yet understood, meaning they could be harmful.