science topic 1 Flashcards
(34 cards)
Define the term matter:
Matter is anything that has mass and takes up space.
Define the term atom:
An atom is the smallest unit of an element that retains the chemical properties of that element.
Describe how substances are composed of atoms:
Substances are made up of atoms, which can be arranged in different ways to form elements, compounds, or mixtures.
The development of the atomic model
- Greek philosophers (400BC) All substances consisted of tiny particles called atoms.
*Dalton (1803): Proposed atoms as indivisible particles. - Thomson (1897): Discovered the electron and proposed the ‘plum pudding’ model.
- Rutherford (1911): Found the nucleus through the gold foil experiment.
- Bohr (1913): Suggested electrons orbit the nucleus in shells.
what was the name of JJ.Thomsons model of the atomic structure
Plum Pudding
Who were the scientist that made a discovery to the atomic model
Greek Philosophers - Democritus - John Dalton, J.J. Thomson, Ernest Rutherford, Niels Bohr
Where can each subatomic particle be found
- Protons (positive charge) in the nucleus
- Neutrons (neutral charge) in the nucleus
- Electrons (negative charge) orbiting the nucleus in shells
what are the different subatomic particles within an atom and what charge they have
- Proton: Positive charge, found in nucleus
- Neutron: No charge, found in nucleus
- Electron: Negative charge, orbits nucleus
Recall that atoms are neutrally charged overall and understand that the number of protons must equal the number of electrons:
Atoms are neutral because the positive protons balance the negative electrons.
atoms different for each element? (T or F)
True
How many nonmetals are there and what are some of them?
there are 23 non metals
which include: hydrogen, Helium, Boron, Carbon, Nitrogen, Oxygen, fluorine, Neon, Silicon, phosphorus, sulphur, chlorine, argon, arsenic, selenium, bromine, krypton, tellurium, iodine, xenon, astatine, radon, ununoctium
identify metalloids on the Periodic Table:
Metalloids are found along the staircase line between metals and non-metals.
Boron (B)
Silicon (Si)
Germanium (Ge)
Arsenic (As)
Antimony (Sb)
Tellurium (Te)
Polonium (Po)
Astatine (At)
Recall that the Periodic Table is organised in Groups (columns) and Periods (rows):
- Groups (vertical columns) show elements with similar properties.
- Periods (horizontal rows) indicate the number of electron shells.
Define the term element:
A substance made of only one type of atom.
Define the term molecule:
Two or more atoms bonded together.
Describe the structure of a lattice:
A repeating 3D structure of atoms or ions.
Recognise that atoms of elements can be found in different structures including as single atoms, molecules, and lattices:
- Single atoms: Noble gases like helium
- Molecules: Oxygen (O₂), Hydrogen (H₂)
- Lattices: Metals like copper or ionic compounds like sodium chloride
what are the molecular elements:
- Oxygen: O₂
- Hydrogen: H₂
Chlorine: Cl₂
- Hydrogen: H₂
Describe substance properties including ductility, malleability, lustre, electrical conductivity, state at room temperature:
- Ductility: Can be stretched into wires
- Malleability: Can be hammered into sheets
- Lustre: Shiny appearance
- Conductivity: Allows electricity/heat to pass through
- State at room temperature: Solid, liquid, or gas
Recognise the common properties of metal elements:
Malleable, ductile, good conductors, solid at room temperature (except mercury - liquid), melt at high temps (except mercury - neg 40)
Recognise the common properties of non-metal elements:
brittle, poor conductors, can’t be polished to be shiny, melt at low temps (except diamond over 1000 degrees)
Identify the noble gases as the Group 18 elements:
Helium, Neon, Argon, Krypton, Xenon, Radon.
Recognise the common properties of noble gases:
Non metal, unreactive, gasses at room temp
Define the term compound:
A substance made of two or more different types of atoms chemically bonded.
