Foundation: C1 - Atomic Structure and the Periodic Table Flashcards
What is a mixture?
Give examples of mixtures.
Two or more elements or compounds that are not chemically bonded.
Examples of mixtures:
Tap water (water and a variety of ions)
Sea water (water and a variety of ions including sodium and chloride ions)
Milk (water and a variety of fats, proteins and sugars)
Steel (iron, carbon and other metals)
What is a compound?
Give examples of compounds.
Two or more elements that are chemically bonded.
Examples of compounds:
Covalent compounds: Carbon dioxide, water, carbon monoxide, methane, sulfur dioxide, nitrogen dioxide etc.
Ionic compunds: Sodium chloride, sodium hydroxide, iron oxide, calcium carbonate etc.
What is the easiest way to identify whether something is an element?
Look in the periodic table.
What is a molecule?
Two or more atoms chemically bonded together.
These can be atoms of the same element (e.g O2) or atoms of different elements (CO2).
What three types of subatomic particle are atoms made from?
Protons
Neutrons
Electrons
What is the charge of a proton?
Positive
+1
What is the charge of an electron?
Negative
-1
What is the charge of a neutron?
Neutral
No Charge
0
What is the overall charge of an atom? Explain why atoms have this charge.
Neutral (no charge, 0)
Because all atoms have equal numbers of positively charged protons and negatively charged electrons, so they cancel each other out.
What is the mass of a proton?
1
What is the mass of an electron?
0 (no mass)
What is the mass of a neutron?
1 (the same as a proton)
Where are protons found in an atom?
In the nucleus
Where are neutrons found in an atom?
In the nucleus
Where are electrons found in an atom?
On the outer shells
How can you work out the number of protons in the atom of a named element (e.g carbon)?
Use the atomic/proton number in the periodic table.
This is the small number.
How can you work out the number of electrons in the atom of a named element (e.g carbon)?
Use the atomic/proton number in the periodic table.
This is the small number.
The number of electrons is always the same as the number of protons.
How can you work out the number of neutrons in an atom of a named element (e.g carbon)?
Mass number - atomic/proton number
The mass number is protons plus neutrons, so if you take the number of protons away from the mass number you are left with the number of neutrons.
Which of the following decides what element an atom is:
- The number of electrons
- The number of protons
- The number of neutrons
- The atomic mass
The number of protons.
For example, if an atom has 6 protons, it must be carbon.
What did Thompson (Plum Pudding Model) suggest the atom was like?
A ball of positive charge with negative electrons scattered in it.
Rutherford realised that the plum pudding model was wrong.
What was Rutherfords model of the atom like?
What did he call his model of the atom?
Rutherford thought the atom was made of a tiny positvely charged nucleus, surrounded by scattered eletrons.
He called it: The nuclear model
How did Bohr improve Rutherford’s nuclear model of the atom?
Bohr realised that electrons orbit the nucleus on shells.
How big is the nucleus of an atom compared to the whole atom?
The nucleus of the atom is 1/10,000 of the size of an atom.
Where is most of the mass of the atom found?
In the nucleus.
Because this is where protons and neutrons are found.
What is an isotope?
The same element (same number of protons) with different numbers of neutrons.
For example, carbon atoms with 6 neutrons and carbon atoms wiith 8 neutrons.
If isotopes have different numbers of neutrons how else must they also be dfferent?
They must have different atomic masses.