C4.1/2 - Atomic & Electronic Structure Flashcards
What four things did John Dalton suggest about atoms?
- All matter is made from atoms
- Atoms cannot be made or destroyed
- All atoms of an element are identical
- elements contain different types of atoms
Who first suggested the theory that everything was made from atoms?
John Dalton in 1803 suggested this. Other scientists had suggested this before but Daltons ideas were more detailed.
Dalton’s ideas were developed into a detailed theory of atomic structure. In 1897, what did J.J Thompson discover in development to Dalton’s original ideas?
In 1897, J.J Thompson discovered that atoms contain even smaller subatomic particles called electrons.
What did Ernest Rutherford discover in 1911 about atoms?
Ernest Rutherford discovered that an atom is mostly empty space with its electrons arranged around a central nucleus.
What did Neils Bohr discover to Rutherford’s theory?
Neils Bohr calculated that electrons move in fixed orbits or shells around the nucleus.
What is the nucleus of an atom made of?
The nucleus of an atom is made up from two subatomic particles called protons and neutrons.
Describe the properties of protons, neutrons and electrons.
- Protons: protons are positively charged
- Neutrons: neutrons have no electrical charge
- Electrons: electrons are negatively charged
Why is an atom electrically neutral?
An atom is electrically neutral overall because it contains equal numbers of protons and electrons.
Most of the mass of an atom is found in the ______.
Nucleus
Name the three subatomic particles
Neutrons, protons and electrons
Which subatomic particle has the least mass? Also state the charge of this atom.
Electrons have the least mass and they are negatively charged.
Which subatomic particle is positively charged and state it’s mass.
Protons are positively charged and it has a mass of 1
Which subatomic particle has no electrical charge and state it’s mass.
Neutrons have no electrical charge and it has a mass of 1
What is the mass of an electron?
0.0005
The atomic number of an atom is the number of _______ it contains.
Protons
The (I) ________ ______ contains information about each
(II) ________, including the atomic number of its atoms.
(I) Periodic Table
(II) Elements
Is the atomic number shown at the bottom of the box or at the top?
The atomic number is always the bottom number
The mass number of an atom is the total number of (I) _______ and (II) ________ it contains.
(I) protons
(II) neutrons
What are isotopes?
Isotopes are varieties of an element that have the same atomic number (same amount of protons), but different mass numbers (different amount of neutrons).
Isotopes are shown by a full chemical symbol e.g 12/6 C.
How would you work out the number of neutrons an isotope has?
The number of neutrons an isotope has it the top number minus the bottom number.
The top number is the mass number(number of protons and neutrons) and the bottom number is the atomic number(number of protons).
How are isotopes named?
Isotopes are named after their element and mass number. For example 12/6 C would be named Carbon-12.
When an atom becomes and ion, it’s nucleus stays the same and so do the numbers of protons and ________.
Neutrons
An ion with a single negative charge has one more electron than the original atom. Why does this make it negatively charged?
This is because there is an imbalance between positively charged subatomic atoms (protons) and negatively charged subatomic atoms (electrons). An extra electron causes the atom to become negatively charged since electrons are negatively charged.
An ion with a single positive charge has one less electron than the original atom. Why does this make it positively charged?
This is because there is an imbalance between positively charged subatomic atoms (protons) and negatively charged subatomic atoms (electrons). One less electron causes the atom to become positively charged since electrons are negatively charged. So now there is one more protons which is positively charged than negatively charged electrons.
What is an element?
🎩 An element is a substance that cannot be broken down
🖕🏿👿🖕🏿 down chemically and it only contains one type of atom.
👕
👖
^^
How many elements are there?
Just over 100 different elements.
No elements have the same _______ number.
Atomic
How are elements arranged in the periodic table?
Elements are arranged in order of increasing atomic number in the periodic table.
What is a compound?
A compound is a substance that contains two or more different elements, chemically combined. Chemical bonds join the elements together in a compound, so the elements are not just mixed together.
What does the chemical formulae show?
The chemical formulae shows the symbols of each element it commits, and the number of atoms of each element. CuSO4 (small 4). It shows that this compound contains copper, sulfur, and oxygen (4 oxygens).
Electrons occupy _____ around the nucleus.
Shells
What is the way that the electrons are arranged in an atom called?
The electronic structure. Different shells can hold a different number of electrons.
How many electrons can the first shell, second shell and third shell hold?
First shell : 2 electrons
Second shell : Can hold up to 8 electrons
Third shell : Can hold up to 8 electrons
