Preview

Chem Notes Igcse

Better Essays
Open Document
Open Document
6684 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Chem Notes Igcse
IGSCE Chemistry Notes

Oxides
Oxides are used to determine whether an element is a metal or a non-metal.
Most non-metals are classed as acidic oxides. While most metals are classed as basicoxides.
Acidic Oxides * Reacts with water to form acids * Neutralises alkaline solution to form salt + water
Basic Oxides * Neutralises acidic solutions to form salt + water
Amphoeteric Oxides * These are non-metals which display both acidic and basic properties
Alkaline Oxides * Reacts with water to form alkaline solutions
Neutral Oxides * Do not display either of the acidic or the basic oxides’ properties.
Giant Covalent Structures
There are 2 examples of Giant covalent structures: Diamond & Graphite
They are both allotropes of carbon, meaning they are both different types of the physical form of Carbon.
Diamond
Structure: Giant covalent lattice of carbon atoms.
Each Carbon atom is bonded to 4 others which tetrahedrally surround the atom.
They have a high melting point as a large amount of heat energy is needed to break their bonds.
They are unable to conduct electricity as they have no free mobile electrons to carry the current.
Diamond is very hard as there are many bonds within the substance. It is the hardest natural substance and is often used in drilling.
Graphite
Structure: Arranged in layers of atoms.
Each carbon atom is joined to 3 others, leaving one outer shell electron on each carbon is free to move and able to cary the current. Therefore, they are able to conduct electricity.
Graphite also has a high melting point for the same reasons as diamond. However, it is not hard like diamond but in fact very soft.
There are weak forces between the layers of atoms. They are able to slide over each other and therefore able to act as a lubricant.

Covalent Bonding
Definition: When an atom shares one or more pairs of electrons between atoms to obtain the electronic configuration of a noble gas.
Covalent bonds appear in

You May Also Find These Documents Helpful

  • Powerful Essays

    Gly1000 Exam 1 Study Guide

    • 3144 Words
    • 13 Pages

    Non-Crystalline – (Ex. Glass) Soften as the temperature increases and have no sharply defined melting point…

    • 3144 Words
    • 13 Pages
    Powerful Essays
  • Satisfactory Essays

    1. Which type of compound usually has higher melting points, ionic compounds or covalent compounds? What is the reason for this difference in melting points? (3 points)…

    • 356 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    ← Occurs in the earth’s crust mainly in two allotropic forms – graphite and diamond…

    • 3348 Words
    • 14 Pages
    Good Essays
  • Satisfactory Essays

    3.06 Lab Worksheet

    • 364 Words
    • 2 Pages

    Ionic bonds typically have much higher melting points than covalent bonds because of their crystal-like structures. The bondage is much more complex and requires higher heat to break than a covalent whose bonds are broken relatively easy.…

    • 364 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    Chem 3.06

    • 511 Words
    • 3 Pages

    Answer: Ionic compounds have a higher melting point the heat needed to break down the bonds between the compounds is much higher than not needing to break down any bonds at all.…

    • 511 Words
    • 3 Pages
    Good Essays
  • Better Essays

    Atoms react with other atoms to gain or lose electrons to fill their outer shell.…

    • 933 Words
    • 4 Pages
    Better Essays
  • Satisfactory Essays

    Experiment E Post Lab

    • 321 Words
    • 2 Pages

    The determined pure melting point was lower than the expected melting point of 241-243 degrees Celsius. This could have been due to the crystalline product not being 100% pure. We know this is true since the determined crude melting point is…

    • 321 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Chem Grade 11 Exam Notes

    • 824 Words
    • 4 Pages

    * Electron Cloud: the region of an atom in which there is a probability that an electron exists…

    • 824 Words
    • 4 Pages
    Satisfactory Essays
  • Powerful Essays

    gr 9 science study notes

    • 1970 Words
    • 8 Pages

    -the movement of electrons within a substance caused by a nearby charged object. There is no direct contact.…

    • 1970 Words
    • 8 Pages
    Powerful Essays
  • Good Essays

    There are many covalent bonds in this structure which would need a lot of energy to break them however the bonds are weak causing the structure to slide over each other making graphite slippery. It can conduct electricity because it contains delocalised electrons. 2. Why does sodium chloride have a higher melting point than water? Sodium chloride is considered as a giant ionic structure because it consists of repeating lattices of ions.…

    • 641 Words
    • 3 Pages
    Good Essays
  • Better Essays

    “Diamonds are formed when carbon deposits are exposed to high pressure and high temperatures for prolonged periods of time.” (Diamonds: Chemistry & Structural Properties, 2012) When these high temperatures and high pressures combine with carbon deposits, a crystal begins to grow. It grows in different shapes such as octahedron, macle, dodecahedron or cubic. Usually diamond growth is a symmetrical structure and the natural form is octahedron, which is an object with eight sides. The depth of the growth can range between 60 to 120 miles down, the pressure is approximately 5 gigapascals and the temperature is can be near 2,200 degrees Fahrenheit. (Diamonds: Chemistry & Structural Properties, 2012) An interesting fact, diamonds can also form under the oceanic crust, although at much greater depths. They also tend to be exposed to the higher pressures and temperatures allowing the crystals to grow larger. (Diamonds: Chemistry & Structural Properties,…

    • 2118 Words
    • 9 Pages
    Better Essays
  • Good Essays

    Adamantine: “ resembling the diamond in hardness or luster” (Merriam-Webster.com). Njinga Mbandi was a diamond, she was unyielding, sharp, and she was made into a formidable queen by pressure. Njinga was the queen of Matamba, Africa for 40 years and she went down in African history as one of the most remembered queens in Africa. She was a quick, sly diplomat, able to negotiate the trickiest of situations. Njinga was also a warrior, ever-ready to defend her people. Her queenhood was one of the most successful in Africa’s history.…

    • 551 Words
    • 3 Pages
    Good Essays
  • Better Essays

    The melting point of a compound is used by organic chemists not only to identify the compound, but also to establish its purity. To determine the melting point two temperatures were noted. The first was the point at which the first drop of liquid formed among the crystals; the second was the point at which the whole mass of crystals turned to a clear liquid. And the melting point was recorded from this range of melting (Pavia, 2005).…

    • 1111 Words
    • 5 Pages
    Better Essays
  • Good Essays

    There are two types of covalent bonding: polar and non-polar. Polar covalent bonds occur when they have an asymmetrical distribution of electrons, whereas nonpolar bonds have a more symmetrical distribution. Polar compounds will contain…

    • 388 Words
    • 2 Pages
    Good Essays
  • Satisfactory Essays

    Covalent bond: A chemical bond formed by the sharing of one or more electrons,especially pairs of electrons, between atoms. A water molecule would be an example of this because each hydrogen atom shares an electron with the oxygen atom.…

    • 338 Words
    • 2 Pages
    Satisfactory Essays