Essential skills
Properties of matter
Separating Techniques: safety procedures
Bring in STAWA textbook:
15th Feb Tuesday
New Topic - Atomic Structure:
Homework:
Onenote - Classification of Matter
STAWA - Set 7, 8 pages 127-129, Set 13 pages 136 -138
Pearson Ch 2: Atoms: structure and mass
What is the structure of an atom?
Protons, neutrons and electrons are not evenly distributed in an atom. Most of the volume of the atom is empty space
Protons and neutrons exist in a dense core at the centre of the atom. This is called the nucleus. It is held together by the strong nuclear force.
The electrons are spread out around the edge of the atom. They surround the nucleus in layers called shells or energy levels.
Electron’s relative mass is approximately 1/1840. - negligible
Relative mass is relative to a proton.
Z = atomic number - its on the bottom
A = atomic mass - number of protons + neutrons.
Isotopes:
Atoms with the same number of protons (element), and a different number of neutrons.
Isotopic ions
Carbon 12 be like
Carbon 14 is radioactive, used in carbon dating.
$A_r$ = $\frac{(RIM + PercentageAbundance)+.....}{100}$
RIM = Relative Isotopic Mass
Classifications of Matter homework:
Q1:
Pure substances:
Mixtures:
Q2:
a) A compound is 2 or more elements chemically bonded together, whereas a solution involves a solute dissolving in a solvent, and are not bonded together.
b) No, a solution is a homogenous mixture. The solute and solvent are not chemically bonded together, so they are not a compound, however they are uniform, so it is homogenous. As it is not a pure substance, it must be a mixture.
c) The salt is a compound. As it both released a metal and a gas, this indicates that it is most likely an ionic compound, comprised of a transition metal, and a gas, Chlorine.
Q3:
Matter:
Homogenous:
Pure substances:
Elements
Compounds
Solutions
Homogenous mixtures
Heterogenous:
Heterogenous mixtures
Q4:
Decanting is a method of separation where gravity is used to separate a solid from a liquid. The liquid is gradually poured out from the solid-liquid mixture.
