elements 1

Cards (36)

  • Non-living things (matter) is made up of small particles called atoms. There are different types of atoms. Each type is an element. We use symbols to identify different elements.
  • Hydrogen atoms consist of 1 electron, 1 proton and 1 neutron

    Helium atoms consist of 2 protons, 2 neutrons and 2 electrons
  • Difference between atoms
    Have different number of protons, neutrons and electrons
  • The structure of atoms
    • Atoms consist of a nucleus and electron orbits
    • The nucleus is made of protons (positively charged) and neutrons (no charge/neutral)
    • Electron orbits contain electrons (negatively charged) particles
  • Periodic table
    Elements are organised in 1 big table called the periodic table
  • In the periodic table elements with similar nature a grouped together
  • Symbols
    • We use symbols to represent elements in the periodic table
    • Each Symbol must start with an uppercase letter to represent the name of the element
    • Symbols have superscript numbers called the atomic mass number. This represents the total number of protons and neutrons in the nucleus of 1 atom
    • Symbols also have a subscript number called the atomic number. This represents the number of protons in 1 atom of the element
  • On your periodic table it's the other way around - the atomic number is on top and the atomic mass number is on the bottom
  • Calculating number of electron, proton and neutron
    1. Atomic number = the number of proton = the number of electrons (note: number of electrons can change)
    2. Neutron = Mass number - atomic number
  • Elements are made entirely of one type of atom e.g: hydrogen element is made entirely of hydrogen atoms
  • Elements are found in the periodic table
  • Each group of elements have unique characteristics, called properties. These properties determine if an element is metal, non-metal or metalloid.
  • Summary of the rules!
    • Atomic number = the number of proton = the number of electrons
    • Atomic mass number = Protons + Neutrons
    • Neutron = Atomic Mass number - atomic number
  • Describe
    Tell me the features, properties, pattern or characteristics of something.
  • Protons and Neutrons are in the nucleus, Electrons are in the orbit
  • Revision questions
    • What are elements?
    • The periodic table lists all the elements; how many elements have been identified to date?
    • How are elements assigned a chemical symbol?
  • Revision questions Answers
    • What are elements? Elements are made of atoms. Every element is made of one type of unique atoms with a specific number of protons and electrons.
    • How many elements have been identified to date? 118
    • How are elements assigned a chemical symbol - unique atoms are discovered (elements is discovered) then assigned a unique symbol to differentiate it from other elements.
  • Elements in the same group share the same number of valence electrons except for helium
  • Groups
    • Elements are arranged into 18 groups, (vertical columns)
    • Groups indicate the number of valence electrons (outer shell electrons) of the atoms in that group
  • Periods
    • The horizontal rows are called periods
    • There are 7 periods
    • Elements in the same period have same number of electron shells or obits
    • Elements in the same period (row) share the same number of electron shells
  • Task: Colour in the groups. And make a key. You'll need 8 different colours!
  • Key
    • Metals
    • Non-Metals
    • Alkali Metals
    • Alkaline Earth Metals
    • Transition Metals
    • Basic Metals
    • Metalloids
    • Non-metals
    • Halogens
    • Nobel Gases
    • Group
    • Period
  • Symbol
    Unique atoms are discovered (elements is discovered) then assigned a unique symbol to differentiate it from other elements
  • Groups
    • Elements are arranged into 18 groups (vertical columns)
    • Groups indicate the number of valence electrons (outer shell electrons) of the atoms in that group
  • Periods
    • The horizontal rows are called periods
    • There are 7 periods
    • Elements in the same period have same number of electron shells or obits
  • Groups
    • Alkali Metals
    • Alkaline Earth Metals
    • Transition Metals
    • Basic Metals
    • Metalloids
    • Non-metals
    • Halogens
    • Noble Gases
  • Metals are differentiated from non-metals on the periodic table
  • Ionization energy
    The amount of energy required to remove an electron from an atom or molecule
  • Atomic radius

    Becomes more tightly packed
  • Reactivity
    • A measure of how easily an element will combine with other elements to form compounds
    • The most reactive groups are group 1 (Alkali metals) and group 17 (Halogens)
  • Steps to drawing atomic structure
    1. Search for the element on the periodic table
    2. Note down its chemical symbol, atomic number and mass number
    3. Calculate the number of protons and electrons
    4. Calculate the number of neutrons
    5. Draw a circle to represent the nucleus and note the number of protons and neutrons
    6. Draw your electron rings and fill them up with the number of electrons
  • 1st shell - max 2 electrons, 2nd shell - max 8 electrons, 3rd shell - 8 (first 20 elements) or 18 depending on the element
  • Metallic Properties
    • Tends to be shiny/lustrous
    • Solid at room temperature except for mercury
    • Good conductors of heat and electricity
    • Malleable (can be hammered into sheets and bent)
    • Ductile (can be stretched into wires)
    • Form positively charged ions
    • Uses: everyday in construction, electronics and jewellery
  • Non-Metals
    • Tends to be dull
    • Does not conduct heat and electricity
    • Break or crumble when you bend them - brittle
    • Form negatively charged ions
    • Uses: Helium gas for balloons, oxygen for respiration
  • Metalloids
    • Share the properties of both metals and non-metals
    • Example: silicon
    • Good conductors of heat and electricity like metals but break easily like non-metals
  • Alkali metals - 20 reactions of the alkali metals with water (royal society of chemistry alkali metals)