atoms Flashcards
All atoms are made up from ____ smaller particles called ____
All atoms are made up from three smaller particles called sub-atomic particles
What are the 3 major subatomic particles of an atom?
Proton, neutron, electron
Describe how particles in an atom are arranged
In the centre of the atom we find the nucleus. This contains the protons and the neutrons.
Around the nucleus, there are electrons moving around the nucleus
Describe what the particles are like (protons have a mass of __ and have a _____ charge)
The protons have a mass of 1 and have a positive (+) charge.
The electrons are very small particles and have almost no mass. They have a negative charge (-)
The neutrons have a mass of 1 and no charge.
Where is the atomic number located on the periodic square thing e.g. hydrogen
The atomic number is the smaller number, located on the bottom. The atomic number can also be the no. of protons
Where is the mass number located and what is it
The mass number is the bigger number located at the top, and is the no. of protons + neutrons.
How do we work out the number of neutrons? Say the mass number is 23 and the atomic number / no. of protons is 11.
23-11=12 neutrons.
Note: atomic number does not always equal number of protons.
Number of protons =
Number of protons = number of electrons
What is the maximum the first shell of an atom can carry? (the first shell is the first circle surrounding the nucleus)
2 electrons
For the first 20 elements in the periodic table, the maximum number of electrons in each shell, going from the middle to the outside, is?
2, 8, 8, 18
In the periodic table, elements are arranged in columns called ___
columns: groups
In the periodic table, elements are also arranged in rows called ___
rows: periods
