C1 Flashcards
definition of ion
Ion = an atom that has gained a charge by gaining or losing electron(s)
where are metals on the periodic table
on the left
where are non-metals found on the periodic table
on the right
what are metalloids
Metalloids = elements with both metal AND non-metal properties
where are metalloids found
The staircase division on the right side shows you where the metalloids are found
what does group number show
Group Number = number of outer electrons
what does the period number show
Period Number = the number of shells in our atom
what is the relative atomic mass
relative atomic mass = the average of the mass numbers of ALL the isotopes of an element, relative to Carbon-12.
definition of isotopes
Isotopes = different forms of the same element, with the SAME number of electrons and protons, but DIFFERENT number of neutrons
what does the mass number show
number of protons and electrons
what does the atomic number show
number of protons or electrons
differences between compound and mixtures (3 each)
compounds-
-chemically combined
-seperated using chemical reactions
-have a fixed ratio
Mixtures
-not chemically bonded
-seperated using seperating techniques
-dont have a fixed ratio
what does aqueous mean
aqeuous = dissolved in water (looks like aqua which means water)
what is the law of conservation of mass
Law of conservation of mass = mass cannot be created or destroyed. –> total mass of the reactants = total mass of the products
define filteration
Filtration = a technique that separates the insoluble substances in a solution from the solvent/ any soluble substances
define soluble
Soluble = ability to dissolve
define solvent
Solvent = a liquid that can dissolve things in it - examples: water, alcohol
define solution
Solution = a solute that is dissolved in a solvent
whatt is the process of crystallisation
Crystallisation is used to separate a solute from a solvent - more specifically the term crystallisation is used when a pure salt is obtained from the salt solution
what is the setup for crystallisation
In crystallisation here is the set up:
A heatproof mat is placed down. On top of this, a tripod is set up with a wire gauze on top, with the metal crucible dish balanced on this gauze. The bunsen burner is placed underneath the tripod. You slowly evaporate the solvent off. Once it looks mostly gone, you tip out the crystals (you may need to scrape them off the dish) onto a paper towel and leave it in a cool dark place to dry for a few days.
breifly describe the set up for distillisation
A bunsen burner is placed under the round bottom flask. The liquid with the lower boiling point starts to become a gas first. Whilst this is becoming a gas, the temperature of the mixture does not change. When it comes a gas, it rises and enters the tube sealed within the bung. Through the tube it enters the condensing chamber, which has constantly flowing cold water running around the tube, which makes this gas condense and flow down to be collected into a beaker.
define condenser in terms of distillation
A condenser = a glass tube with cold water flowing around it
define miscible liquids
Miscible liquids = liquids that can dissolve in each other mixing completely, like milk and water
what happens to things with higher boiling points in a fractionating column
Things with higher boiling point condense on the cool beads near the bottom and drips back into the flask
define immiscible liquids
Immiscible liquids = liquids that can’t dissolve in each other like water and oil
what is a fractionating column
A laboratory fractionating column is a piece of glassware used to separate vaporized mixtures of liquid compounds with close volatility. Most commonly used is either a Vigreux column or a straight column packed with glass beads
what is paper chromatogaphy used for
Paper chromatography is used to separate dyes.
what does paper chromatography depend on
Paper chromatography uses the different solubility of these dyes to do this.
define solubility
Solubility = the ability of something to dissolve
what does solubility in chromatography determine
The solubility of the dye/ink determines how far that dye travels with the water up the paper
how must the paper be dipped into the water
The paper must be dipped below the pencil line so that the ink spot does not dissolve into the solvent pool.
what did john Dalton discover about the atom
John Dalton - said substances were made out of tiny hard spheres - each chemical element had its own atoms which differed in mass, and these were the fundamental building blocks of nature
what had JJ Thompson discovered?
JJ Thompson (1800s)- discovered the electron
Thompson came up with the plum pudding model (plum pudding is basically a raisin cake). Plums were electrons, in a ball of positive charge (the pudding).
how was the nucleus discovered
The nucleus was discovered in the gold foil experiment
Niels Bohr came up with with the modern nuclear model and said electrons must be orbitting the nucleus (modern nucleus = nucleus in middle with circles around it)
what did James Chadwick discover
James Chadwick discovered the neutrons to explain the missing mass
wha did the result of the gold foil experiment prove
The results of the gold foil experiment told Rutherford Geiger and Marsden that:
1)Most of the atom is empty –> most of the alpha particles went straight through
2)The nucleus is a positive charge at the centre of the atom –> some of the alpha particles partially refracted
3)The nucleus is very dense and small in the middle of the atom –> a small number of alpha particles refracted completely
what are sub-atomic particles
Sub-atomic particles = electrons protons and neutrons
what are the masses of protons,electrons and nuetrons
Masses of:
electron: negligible - 1/1840
Proton: 1
Neutron: 1
what are the charges of the sub atomic particle
Charges of:
electron: -1
proton: +1 (p for positive)
neutron: 0 (NEUTRon for NEUTRal)
SO the overall charge of the nucleus is positive
what is the charge of an atom
An atom has a neutral overall charge. All atoms have an equal number of protons and electrons. This means that the total positive charge and the total negative charge is equal, so they cancel each other out, leaving an overall atomic charge of 0.
in the periodic table what is the top number and what does it mean
In the periodic table, the top number is the relative atomic mass. Relative atomic mass = the average mass of all the isotopes for that element, relative to the mass of Carbon-12
what does group number and period number show
Group number = the number of outer electrons
Period number = the number of shells
what are chemical properties of an atom determined by
Chemical properties are determined by the number of outer electrons
