C1 - Atoms Flashcards
What is an ELEMENT?
A substance containing only one type of atom.
What is a COMPOUND?
A substance containing 2 or more types of atoms chemically bonded.
Why do equations have to be BALANCED?
-CONSERVATION OF MASS, atoms can neither be created or destroyed in a reaction.
What is a MIXTURE?
A mixture consists of different substances not chemically bonded.
What is FILTRATION?
Removes large insoluble particles from a liquid.
What is CRYSTALISATION?
Leaves behind crystals of a dissolved substance (solute) when heated gently.
What is DISTILLATION?
Condensing an evaporated solvent and then collecting it.
What is CHROMATOGRAPHY?
Causes substance to rise up CHROMATIC paper due to CAPILLARY ACTION.
Name the 5 different phases between the states of matter
Solid -> Liquid is called melting
Liquid -> Gas is called boiling
Gas -> Liquid is called condensing
Liquid -> Solid is called freezing
Solid -> Gas is called sublimation
What are the properties of a SOLID?
-Regular arrangement/lattice
-Vibrate about a fixed position
-Cannot be compressed
What are the properties of a LIQUID?
-Not in a regular arrangement
-Move past each other
-Cannot be compressed
What are the properties of a GAS?
-Particles are far apart
-Move randomly at fast speeds due to HIGH ENERGY
-Can be compressed
What is needed for particles to be melted/evaporated?
ENERGY (heat) is needed to overcome the ELECTROSTATIC forces of attraction between particles.
What is a PHYSICAL CHANGE?
No new substance is made.
What does (aq) or AQUEOUS mean?
AQUEOUS means a substance that is dissolved or in a solution.
What did JJ Thompson create?
The PLUM PUDDING MODEL - consisted of a positive charge with electrons.
What did Ernest Rutherford discover?
He discovered that the nucleus was SMALL and positively charged - electrons must orbit far away.
What did Neils Bohr discover?
Discovered that electrons exist in SHELLS.
What did James Chadwick discover?
Determined that the nucleus must contain both neutrons and protons.
State the CHARGE and MASS of electrons, protons and neutrons.
Electron Charge; -1
Electron Mass; 0
Proton Charge; +1
Proton Mass; 1
Neutron Charge; 0
Neutron Mass; 1
What is the RAM?
RAM is the number of both protons and neutrons.
What is the ATOMIC NUMBER?
ATOMIC NUMBER is the number of protons + electrons (same amount as they balance each other out).
What is an ISOTOPE?
Same element, different number of neutrons.
How was the periodic table originally ordered?
Elements were originally ordered according to their ATOMIC WEIGHT; some elements were then grouped together if they shared similar properties but still followed the ATOMIC WEIGHT pattern.
