Ch3: Atomic structure Flashcards
How many sub-atomic particles found inside atoms?
- protons, neutrons, electrons.
Charge of neutron
0/neutral
Charge of proton
Positive / +1
Charge of electron
-1 / negative
What are found in the centre of the atom?
Protons and neutrons in the nucleus
relative mass of electron
Negligible mass
Relative mass of neutron
1
Relative mass of proton
1
The electrons move …. around the nucleus
Rapidly
How to find number of electrons with atomic number
Same as atomic number/proton number
What is the nucleon number
Mass number of an element – total number of protons and neutrons in its nucleus
Why is an atom always electrically neutral
Number of protons = number of electrons thus charges cancel out
What is an ion?
1. The charge
2. Form when…
An atom or group of atoms with positive or negative charge, and forms when atoms lose or gain electrons to obtain a fully-filled outer shell.
Metal atoms…. from their outermost shell when they form ions
Lose electrons
The ions formed are positive, with _____ protons than electrons
More
Non-metal atoms ____ electrons when they form ions
gain
When mon-metal atoms gain electrons, they are _____ because…
Negative because they have more electrons than protons
Isotopes are atoms of ______ with the same number of _____ and _____, but different number of ______.
Same element, protons and electrons, neutrons
Isotopes of an element have:
Same/different atomic number
Same/different nucleon numbers
Same, different
Isotopes have identical _____ properities
Chemical
Isotopes are differing in melting and boiling points, solubility, density, etc. -> _____ properties
Physical
Isotopes have different physical properties because of their different _____
Masses
The _____ -charged electrons move around the nucleus in electron shells
Negatively
Elements with _____ of valence electrons belong to the ______ group in the periodic table.
Same, same