periodic table Flashcards
what is the structure of the atom
The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged).
what is a proton? what size is it? where can it be found?
positively charged particle, smallest subatomic particle, found in the nucleus of an atom
what is a neutron? what size is it? where can it be found?
neutrally charged particle or particle with no charge, heavey and weighs the most, found in nucleus of an atom
what is an electron? what size is it? where can it be found?
negatively charged particle, weighs the least, found in the shells of an atom
The electron configuration of Hydrogen
1
The electron configuration of Helium
2
The electron configuration of Lithium
2, 1
The electron configuration of Beryllium
2, 2
The electron configuration of Boron
2, 3
The electron configuration of Carbon
2, 4
The electron configuration of Nitrogen
2, 5
The electron configuration of Oxygen
2,6
The electron configuration of Fluorine
2,7
The electron configuration of Neon
2,8
The electron configuration of Sodium
2, 8, 1
The electron configuration of Magnesium
2, 8, 2
The electron configuration of Aluminum
2, 8, 3
The electron configuration of Silicon
2, 8, 4
The electron configuration of Phosphorus
2, 8, 5
The electron configuration of Sulfur
2, 8, 6
The electron configuration of Chlorine
2, 8, 7
The electron configuration of Argon
2, 8, 8
The electron configuration of Potassium
2, 8, 8, 1
The electron configuration of Calcium
2, 8, 8, 2
groups
vertical
periods
horizontal
What is common among elements in the same group?
They have the same number of valence electrons
as a result, they will all have the same chemical reactivity.
What is common among elements in the same period?
have the same number of shells
What are isotopes?
Isotopes are atoms of the same element with different mass numbers. They have the same number of protons, but different numbers of neutrons. Isotopes can also be stable or unstable. Unstable isotopes decay to form other elements.
What causes radioactivity to emit from isotopes?
when an isotope is unstable it becomes radioactive and is called radioisotopes. can be emitted naturally or artificially.
The number of natural isotopes which exist.
around 50
Calculation of the half-life of an isotope < half-life of an isotope
Half-life is the time it takes for a substance to reduce to half of its initial amount. The nuclei of different radioactive substances decay at different rates. - the amount of time for an isotope to become half of its original amount. example half-life of strontium-90 is 28 years. This means that if you start with 1000g of strontium-90, after 28 years, you’ll have 500g.
what are alpha particles? what is alpha decay?
an alpha particle is a cluster of 2 protons and 2 neutrons, it is heavy and moves slow. alpha decay is when a nucleus ejects an alpha particle, once this happens the original atom turns into a new atom. as an alpha particle is quite big it cannot go through things and bounces off objects and people.
what are beta particles? what is beta decay?
beta particles are very small and negatively charged. beta decay is when the nucleus ejects a beta particle. the original atom changes from being negatively charged to positively charged when this happens, changing the atomic number by 1 and forming a new element. beta particles can go through many objects and people but can’t go through aluiminum
what are gamma rays? what is gamma decay?
gamma rays are a ray of light, it is very small and moves very fast. it can go through most things but can’t go through lead. gamma decay is when a nucleus ejects a gamma-ray, when this happens the protons and neutrons in the original atom rearrange themself inside the nucleus
Valencies of the groups of the periodic table.
group 1 = 1 group 2 = 2 group 3 - 12 = 2 group 13 = 3 group 14 = 4 group 15 = 5 group 16 = 6 group 17 = 7 group 18 = 8
cations
positively charged
anions
negatively charged
How to combine cations (positive charge) with anions (negative charge) to create a compound (drop & swap method).
write down the charge of each element, cross them over, don’t write down the ones, put brackets around elements with brackets excluding the charge from the brackets
How to name different compounds
writing the name of the cation first followed by the name of the anion.
covalent bond
A covalent bond is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms.
ionic bond
Ionic bonding is the complete transfer of valence electron(s) between atoms. throwing out the valence electrons to get 8 in the valence shell.
