C1 Flashcards
What are isotopes
Different forms of the same element which have same number of protons but a different amount of neutrons
How is the periodic table arranged
In columns called groups
What are all atoms made out of
Nucleus and electrons orbiting around
What are reactants
Substances you start with
What are products
New substance made
What does (s) mean
Solids
What does (L) mean
Liquid
What does (g) mean
Gas
What does (aq) mean
Aquous solutions
What are the differences between compounds and mixtures
- compounds have a fixed composition, whereas mixtures dont
- chemical reactions must be used to seperate elements in a compound, whereas mixture can be seperated more easily
- chemical bonds in compounds, but mixtures dont
What is filtration
A technique to seperate substances that are insoluble in a particular solvent. Eg sand in water, salt ect
What is distillation
A solution is heated and boiled to evapourate the solvent. Vapour is given off then enters a condenser. Thisnis an outer glass tube with water flowing through it that acts as a cooling a jacket
Who had the early ideas of an atom
John dalton, he suggested that substances were made up of atoms that were tiny hard spheres.
Who had evidence for electrons in atoms
JJ Thomson, a tiny negatively charged patricle that was found to have a mass about 2000 times smaller than the lightest atom
Who had evidence for the nucleus
Geiger and Marsden, they were doing an experiment with radioactive particles . They were firing positively dense chagred particles called alpha patricles at the thinnest piece of gold. They thought that this laser would go through the gold foil. But the results changed it, some parts pf the laser reflected showing that there was a positive centre of the atom which is called the nucleus
Who made the plum pudding diagram
JJ Thomson
Relative charge of a proton
1
Relative charge of neutron
0
Relative charge of electron
-1
Relative mass of proton
1
Relative nass of neutron
1
Relative mass of electron
Very small
How to find mass number
Add number of protons and neutrons of the atom
How to find number of neutrons
Mass number - atomic number
What is an ion
When an atoms gains one or more electron it becomes negative. If loses electrons then its positive ion
How to find amount of protons and electrons in a element
Bottom number has the same amount of protons and electrons, for eg sodium (na) has 11 protons and neutrons
How to find amount of neutrons
Mass number (top number) - atomic number (bottom)
What are isotopes
Atoms of the same element with different number of neutrons are called isotopes
What are group 0 in a periodic table called
Noble gasses
