C1, Atomic Structure Flashcards
Compounds =
Substances that contain more than one type of atom
Elements =
Substances that contain only one type of atom
Groups are the. (column)
Vertical column
Periods are. (Columns)
Horizontal columns
What do groups in a periodic table contain
Elements with similar chemical properties
What are reactants
The substances you start with
What are products
The substances that are made
What does decomposes mean
To break down
What is the total mass of products formed equal to
The total mass of the reactants
What is a mixture
Two or more substances that are not chemically combined together
What are compounds
Two or more substances that are chemically combined together
What is filtration
The separation of an insoluble substance from a soluble substance in a solvent by using filterpaper
What does soluble mean
Able to dissolve especially in water
What does insoluble mean
Unable to dissolve
What is crystallisation
The process of Separating the filtrate from the solvent
How does crystallisation work
Heat and evaporating dish containing a soluble substance and crystals will form
The rest of the water will evaporate and leave the filtrate on its own
What is distillation
The process to collect the solvent it self instead of evaporating in the air during crystallisation
Method for fractional distillation
1) Mixture is heated
2) miscible liquid evaporates as it turns from a liquid to a gas
3) the gas of the miscible liquid passes into the condenser and is cooled
4) it turns from a gas to a liquid
5) The miscible liquid is collected
What is paper chromatography used for
Used to separate and identify substances from mixtures in a solution
How is paper chromatography able to work
It works as some compounds will dissolve better than others in the solvent
John Dalton’s discovery
He described atoms as solid spheres and said that different spheres were made up by different elements
JJ Thompson’s discovery
Concluded atoms were not solid spheres and he measured the charge and mass and showed atoms must have negatively charged particles
He made the plum pudding model showing atoms as a ball of positive charge with electrons stuck in it
Rutherford’s discovery
Showed plum pudding model was wrong from alpha particle scattering experiment
Rutherford made nuclear model where a positively charged nucleus was where most mass was concentrated and a cloud of negative electrons were around it
what happened in the alpha particle scattering experiment
- They fired positively charged alpha particles at thin sheet of gold.
- They were expecting particles to pass through the sheet or be deflected at most.
- someone deflected backwards so proved the plum pudding model couldn’t be right
Bohr’s discovery
He made a model that suggested all electrons were contained in shells
He said the shells would orbit the nucleus in fixed position
Relative charge and relative mass of protons neutrons and electrons
Protons : +1 relative charge. : relative mass of 1
Neutrons : 0 relative charge. : relative mass of 1
Electrons : -1 relative charge. : relative mass of 1/1836
What is the atomic number equal to
The number of protons in the elements
How to find out the number of neutrons
Mass number - atomic number
What is an ion
Charged atom positive or negative
How are positive ions formed
When atoms lose electrons
How are negative ions formed
When atoms gain electrons
What are isotopes
Atoms of the same element with different numbers of neutrons
What do ions have in common with the original atom
They have the same chemical properties but there physical properties may differ e.g. density
