1) Atomic Structure and Isotopes Flashcards
Define isotopes.
Atoms of the same element with different numbers of neutrons and different masses.
What is the structure of an atom?
- The atom consists of a nucleus made up of positive protons and neutral neutrons.
- Surrounded by negative electrons occupying shells around the nucleus.
What is the relative charge of the: proton, neutron, and electron?
Proton: +1
Neutron: 0
Electron: -1
What is the relative mass of the: proton, neutron, and electron?
Proton: 1
Neutron: 1
Electron: 1/1836
Why is the overall charge of an atom 0?
The total positive charge of the protons is cancelled out by the negative charge of the electrons.
What is meant by mass number, A?
Number of protons + number of neutrons.
What is meant by atomic number, Z?
Number of protons.
Why do isotopes have the same chemical properties as their original atoms?
Because they have the same number of electrons in their outer shell.
What is an ion?
An atom with a net charge.
What are cations?
Positive ions - atoms with fewer electrons than protons.
What are anions?
Negative ions - atoms with more electrons than protons.
Define relative isotopic mass.
The mass of an isotope compared with 1/12th of the mass of carbon-12.
Define relative atomic mass.
The weighted mean mass of an atom of an element compared to 1/12th of an atom of carbon-12.
How could you predict the charge of an ion from its position on the periodic table?
- Atoms of metals on the left of the periodic table lose electrons to form cations.
- Atoms of non-metals on the right of the periodic table gain electrons to form anions.
What does the state symbol (g) mean?
Gas.
