Basics Flashcards
Crucial parts of mendeleevs design
Left gaps
Arranged in rows with similar properties
Creator of periodic table
Dimitri Mendeleev
Mendeleevs prediction
Gallium (eka- aluminium) estimated properties based on gaps
Relative mass of an electron
1/1840
Number above element and what it means
Mass number .protons + neutrons
Number below element and what it means
Atomic number , number of protons
Isotope definition
Same atom, different number of neutrons
Ion definition
Atom or group of atoms with a positive or negative charge
In which groups is the ionic charge linked to the group number
1 and 2
-ide
When non metal atoms form ions
Ionic bonds
Between negatively non metals and positively charged metals
Ionic compounds are always
Electrically neutral
Charge and symbol of ammonium
[Nh4]+
Charge and symbol of sulfate
(So4)2-
Charge and symbol of carbonate
(Co3)2-
Charge and symbol of oxide
(O)2-
Charge and symbol of nitrate
(No3)-
Charge and symbol of hydroxide
(Oh)-
-ate
Shows presence of oxygen
Ionic compound arrangement
Lattice structure
Significance of ionic bonds
Strong electrostatic forces from oppositely charged atoms
Conditions required for conductivity
Must contain charged particles that are free to move
Ionic substance conductivity
They are charged but held in the lattice, they can only move when aqueous or molten
Typical melting boiling points of ionic compounds
High due to lattice and strong electrostatic forces
Definition of salt
Product of acid and alkali
A reaction from which an insoluble solid is produced from 2 soluble substances
Precipitation
Separating a salt
Filtration followed by washing and drying
All nitrates are
Soluble
Most carbonates are
Insoluble (except sodium,potassium and ammonium)
Most hydroxides are
Insoluble (except na, k and ammonium)
Barium meals
Barium sulfate ingested and x ray taken , most other barium salts are toxic,
Why is barium sulfate ok to eat
It’s insoluble so it doesn’t enter the blood
Sodium flame colour
Yellow
Potassium flame colour
Lilac
Calcium flame colour
Red
Copper flame colour
Green-blue
Test for chloride ions
Precipitation test, drops of dilute nitric acid added, shaken. Drops of silver nitrate added, white precipitate of silver chloride formed
Test for sulfate ions
Drops of dilute HCL added, shaken. Barium chloride added, white precipitate barium sulfate forms.
Carbonate test
Limewater turns cloudy when co2 is bubbled through
Non metal to non metal bond
Covalent bond
Properties of simple covalent substances
Low melting
Low boiling
Weak forces between molecules
Properties of giant molecular covalent substances
High melting/boiling
Strong bonds
Differences and similarities between diamond and graphite
Similarly high boiling/melting
Graphite soft diamond hard
diamond doesn’t conduct because no free e
Graphite conducts because one free e each
Immiscible
Can’t mix permanently
How to separate Immiscible liquids
Separating funnel, denser liquid bottom leaves first
Rf value
Solubility, distance moved by compound/distance moved by solvent
Uses of chromotography
Detecting fakes, forensics, food colouring id,
