CAT and Recall revision - January 2023 Flashcards
Name the three sub atomic particles
Proton, Neutron and electron
What is the relative charge of a proton?
+1
What is the relative charge of a neutron?
0
What is the relative charge of a electron?
-1
Why do atoms have no overall electrical charge (are neutral)?
The number of positive proton equals the number of negative electrons so charges cancel out.
What does the atomic number tell you?
Number of protons
What makes an atom of an element the element it is?
The protons
What makes atoms of elements different to each other?
They have a different number of protons
What is the relative mass of a proton?
1
What is the relative mass of a neutron?
1
What is the relative mass of a electron?
1/1840 (Almost 0)
What is mass number?
The sum of the protons and neutrons in an atom
What is an isotope?
The same element with the same number of protons but different numbers of neutrons
Why is the relative atomic mass of chlorine not a whole number?
It has more than one isotope
How do the chemical properties of an isotope differ?
Doesn’t/does have the same number of electrons
How do you work out the number of protons
Use the atomic number
How do you work out the number of electrons in an atom
Same as the protons
How do you work out the number of neutrons
Mass number - atomic number
What do the electrons occupy in an atom
The lowest available energy levels.
How many electrons are there found in shells 1,2 and 3?
2,8,8
What sub atomic particle is involved in bonding (chemical reactions)?
Electrons
What holds atoms of elements together in compounds?
Chemical bonds
How were early periodic tables arranged? (Newland and Mendeleev)
Atomic weight
metal + oxygen=
metal oxide
metal + water =
metal hydroxide + hydrogen
What does the group number tell you?
The number of electrons in the outer shell.
What does the period number tell you?
the amount of shells
metal + chlorine =
metal chloride
What is distillation?
separating soluble substances from a solution.
What is fractional distillation?
separating a mixture of substances with different boiling points
What is filtration?
separating an insoluble solid from a liquid
What is chromatography?
separating coloured components from a mixture.
What charge are alpha particles?
positive
Before electrons were discovered, atoms were thought to be what?
tiny spheres
What subatomic particle was discovered first?
electron
What is a molecule?
a group of atoms
Five ways to separate a mixture
simple distillation, filtration, chromatography, fractional distillation and crystallisation.
Where is the electron found?
in the shell/energy levels
What is group 0 called?
Noble gases
What is group 7 called?
Halogens
What is group 1 called?
Alkali metals
As you go down group 1 the atoms become ______ as they have got more ______.
bigger,shells
What do metals want
to loose an electron
What do non-metals want
to gain an electron
What did Mendeleev do in his periodic table? (3)
- left gaps for undiscovered elements
- added more columns
- predicted the new elements and where they would go
What was the plum pudding model?
JJ Thompsons model that atoms are positive balls of charge with electrons embedded within.
What was Democritus’ theory of the atom?
That atoms are the smallest particles and cannot be divided any further.
What was Ernest Rutherford’s theory?
The electrons obits a large ball of concentrated mass (nucleus).
What was Niels Bohr’s theory?
The electron orbits in spherical orbits around the nucleus.
What did James Chadwick discover in the nucleus?
Neutrons
How did Newlands arrange is elements?
Atomic mass
What is a displacement reaction?
When the more reactive element displaces the less reactive.
