These are detailed Revision Notes for Topic 2.1 of AQA A-Level Chemistry (Periodicity). They were written by me using a combination of the textbook and class notes. I will also be uploading the other topics and creating bundles.
Topics Included:
- Periodic Table
- Trends in the properties of eleme...
AQA A-Level Chemistry 1.7 Oxidation, Reduction and Redox Reactions
Todos para este libro de texto (25)
Escuela, estudio y materia
A/AS Level
AQA
A Level Chemistry
Unit 3.2.1 - Periodicity
Todos documentos para esta materia (25)
Vendedor
Seguir
emilysarahjudge
Comentarios recibidos
Vista previa del contenido
Periodicity
8.1 The Periodic table
8.1 The Periodic Table
- Elements are arranged in order of 8.2 Trends in the properties of elements in period 3
increasing atomic number. 8.3 more trends in the properties of the elements of period 3
- Columns are groups, rows are periods.
- Elements whose outermost electrons 8.4 a closer look at ionisation energies
occupy an s-subshell make up the s-
block. The same goes for p, d and f blocks.
- The periods indicate the number of the highest energy electron shell in an element’s atom.
- Transition metals and d-block elements are not the same thing. Scandium and zinc are not transition
metals because they do not have partially filled 3d orbitals when forming a compound
- The placings of hydrogen and helium vary from table to table:
o Hydrogen is usually placed above group 1 however it is not like them because it is a gas not a
metal. It is an s-block element because of its electronic configuration. It can also become H-
giving it some properties of the halogens.
o Helium is usually placed above the noble gases because it has a full outer shell however it is not
a p-block element.
8.2 Trends in the properties of elements in period 3
- Sodium, magnesium and Aluminium (Groups 1, 2 and 3) are metals with giant structures, they lose
electrons to form ionic compounds.
- Silicon (Group 4) has 4 electrons in the outer shell which form 4 covalent bonds. It has some metallic
properties and is classed as a semi metal.
- Phosphorus, Sulfur and Chlorine (Groups 5, 6 and 7) are non-metals. They either accept electrons to
form ionic bonds or share electrons in covalent bonds.
- Argon (Group 8/0) is a noble gas with a full outer shell and is unreactive.
- Melting and Boiling Point Trends:
o Giant structures on the left have high melting points and molecular or atomic structures on
the left have low melting points.
o Melting points increase from Sodium to Aluminium because of the strength of the metallic
bonding, the charge on the ion increases so there are more delocalised electrons holding the
giant lattice together.
o Silicon is macromolecular meaning it has a very strong covalent structure, giving it a high
melting point.
o Phosphorus, sulphur and chlorine are simple covalent molecules held with weak van de Waals
forces, giving them relatively low melting points.
o Argon has very weak van der Waals forces, giving it a very low melting point.
Group 1 2 3 4 5 6 7 8/0
Element Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Melting 371 922 933 1683 317 392 172 84
Point, K
Boiling 1156 1380 2740 2628 553 718 238 87
Point, K
8.3 More trends in the properties of the elements in period 3
- The atomic radius decreases across a period. This is because along the period there are more protons and
more electrons. The increased positive charge pulls the electrons closer to the nucleus, and there are no
additional electron shells to provide more shielding.
- The atomic radius increases down a group because it has an extra shell of electrons.
Los beneficios de comprar resúmenes en Stuvia estan en línea:
Garantiza la calidad de los comentarios
Compradores de Stuvia evaluaron más de 700.000 resúmenes. Así estas seguro que compras los mejores documentos!
Compra fácil y rápido
Puedes pagar rápidamente y en una vez con iDeal, tarjeta de crédito o con tu crédito de Stuvia. Sin tener que hacerte miembro.
Enfócate en lo más importante
Tus compañeros escriben los resúmenes. Por eso tienes la seguridad que tienes un resumen actual y confiable.
Así llegas a la conclusión rapidamente!
Preguntas frecuentes
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
100% de satisfacción garantizada: ¿Cómo funciona?
Nuestra garantía de satisfacción le asegura que siempre encontrará un documento de estudio a tu medida. Tu rellenas un formulario y nuestro equipo de atención al cliente se encarga del resto.
Who am I buying this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller emilysarahjudge. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for $4.12. You're not tied to anything after your purchase.
