Atomic structure and periodic table Flashcards
Definition of an atom
An atom is the smallest particle of an element that has the properties of that element
How many different elements are there
118
What is pure metal
A metal that is made up of one type of atom
What are atoms made up of
Protons
Neutrons
Electrons
What is the nucleus made of
Protons and neutrons
What are the layers called around the nucleus
Shells
What are the two important properties of protons neutrons and electrons
The mass and electrical charge
What is the mass and electrical charge of a proton neutron and electron
Proton Mass 1 Charge +1 Neutron Mass 1 Charge 0 Electrons Mass almost 0 Charge -1
What charge does the atoms of an element have
They have no overall charge because the element contains equal numbers of protons and electrons
What charge is the nucleus
Positive because the nucleus is made up of protons and neutrons since neutrons have a charge of zero protons have a charge of +1 it will be protons
If the number of protons change in an atom what happens to the atom
It becomes a different element
What is the number of protons in an atom known as
The atomic number or proton number
How do you know what the atomic number is on the periodic table
It is normally the smaller of the two numbers next to the element
How can you find the mass number in the periodic table
It is usually the larger of the two numbers next to the elements
What is the mass number equation
Number of protons + the number of neutrons
What are isotopes
Atoms that have the same number of protons which is every atom that have different number of neutrons
What are the chemical properties of an isotope
They are identical to each other because they have the same number of protons and electrons and an uncharged neutron makes a little different to chemical properties
What are the physical properties of an isotope
They are similar to the normal atom apart from the melting point and boiling point is different
What does RAM stand for
Relative atomic mass
Definition of relative atomic mass
The relative atomic mass of an element is the weighted average mass of the atom of the element measure the relative to 1/12 the mass of a carbon 12 atom
How do you workout the relative atomic mass
It is an average which means you take the atomic number of each isotope and multiply it by the percentage of how much there is in the world then divided by 100 and you get your answer
Is which shell is filled fast with electrons
The ones closest to the nucleus
Are Filled electron shells stable
Yes
What are the columns in the periodic table
Groups
What are the rows in the periodic table called
Periods
Where do elements in period one have their electrons
They only have the electrons in the first shell
What is the maximum number of electrons the first shell can hold
Two
Do elements in period two have a complete first shell
Yes
What happens to the electrons as you go across the periods from left to right
Each element from left to right goes up one electron at a time lithium having to on the first shell and one on the second carbon having two on the first shell and four on the second flooring having two on the first shelf and seven on the second
What is the maximum number of electrons the second shell can have
8
What is the maximum number of electrons the third shell can have
8
What is the maximum number of electrons the fourth shell can have
2
What is the trend of the electrons when you look at a group
The number of electrons on the outer shell is the same and the number of complete electron shells increases by one
What is the number of the group the same as
The number of electrons in the outer shell except for group 0
What is the same about elements in the same group
They have similar properties because elements in a group have the same number of electrons in the outer shell answer react in a similar manner
What is an ion
An atom or group of atoms that has an electrical charge either positive or negative
How do atoms become ions
Atoms have an equal number of protons and electrons and so do not have an overall charge atoms with incomplete outer electron shells are on stable but are the gaining or losing outer electrons in atoms can obtain full outer electron shells and become stable when this happens atoms have an equal number of protons and electrons and so have an overall charge this is called an ion
Call the number of protons and the number of electrons eqaul
Yes
Can atoms gain or lose protons
No
What are negatively charged irons called
Anions
What are positively charged ions called
Cations
What is a compound ion
An ion made up of a group of atoms
What are the two common types of ions
- IDE ions
- ate ions
What is the difference between -ide ions and -ate ions
- ide ions a generally negatively charged ions
- ate ions a generally posotively charged
What is the exception to the -ide ions and the -ate ions
The hydroxide ion which contains hydrogen and oxygen
What atoms are present in hydroxide and what is the charge
1 oxygen
1 hydrogen
-1
What atoms are present in sulphate and what is the charge
1 sulfur atom
4 oxygen atoms
-2
What atoms are present in nitrate and what is the charge
One nitrogen atom
Three oxygen atom
-1
What atoms are present in carbonate and what is the charge
One carbon atom
Three oxygen atoms
-2
What atoms are present in ammonium and what is the charge
One nitrogen atom
Four hydrogen atoms
+1
What did Democritus discover and when was he alive
He thought what if he could keep on chopping a piece of bread in half and came up with the idea of an atom a spherical tiny atom he was alive in 400 BC
What did John dalton discover and when was he alive
All elements are made up of atoms atoms of the same element all the same atoms of different elements or different sizes and masses compounds are formed by two or more atoms join together he was alive in 1803
What did JJ Thompson discover and when was he alive
He discovered the atom has negatively charged particles he concluded that there would also have to be positively charged particles to balance out the negatively charged particles in the atom book never find them as He discovered the atom has negatively charged particles he concluded that there would also have to be positively charged particles to balance out the negatively charged particles in the atom but can never find them as a result he purpose the pump putting model of atoms with electrons in a positively charged see much like plum pudding. He was alive in 1897
What did Ernest Rutherford discovered and when was he alive
He concluded experiment firing positively charged alpha particles at a thin sheet of gold to see what would happen to the atoms in the gold he expected most of the particles to pass through unaffected and a few being deflected by the interaction with the negatively charged particles however much to his amazement he discovered that some of the particles bounce back he concluded that an atom must be mostly empty space with a small dense positively charged particle in the centre surrounded by negatively charged electrons he was the 1st to observe protons he was alive in 1908
What did Niels Bohr discover and when was he alive
He realised the electrons in a cloud around the nucleus of an atom would be attracted to the positive nucleus and would cause it to collapse he suggested that electrons orbit the nucleus in thick shells with each shell being a fixed distance from the nucleus he was alive in 1913
What did James Chadwick discover and when was he alive
He carried out an experiment that provided evidence for neutral particles in the nucleus called the neutrons this resulted in a model of the atom which was pretty close to the modern day except version known as the nuclear model with protons and neutrons as the nucleus and electrons orbiting the nucleus in shells fixed proportions away from the nucleus he was alive in 1932
When was Dmitri Mendeleev alive
1834-1907
How did mmendeleev contribute to the periodic table
He arranged the 50 known elements by atomic weight but made sure they were grouped with similar properties he left gaps for undiscovered elements and predicted what there properties were a few years later he found his predictions were correct he also made a hole new group the noble gases
In what order did Mendeleev originally set out the elements
By atomic mass
