The Atom Flashcards
Includes Big Bang Theory, The Life Cycle of Stars, Simple Atomic Model, Isotopes, Mass Spectrometry, Nuclear Fusion
Where is most of the mass of an atom concentrated?
The nucleus
What is the diameter of the atomic nucleus compared to the atom as a whole?
Small
What takes up most of the space in an atom?
Electrons in their shells
What two types of particles are in the nucleus?
- Protons
- Neutrons
What is the relative charge of a proton?
+ 1
What is the relative charge of an electron?
-1
What is the relative charge of a neutron?
0
What is the relative size of a proton?
1
What is the relative size of a neutron?
1
What is the relative size of a electon?
1/2000
What is the symbol for mass number?
A
Which number is the mass number on an element in the periodic table?
The top one
What is the symbol for atomic number?
Z
Which number is the atomic number on an element in the periodic table?
The bottom one
What is the mass number of an element?
The sum of its protons and neutrons
What is the atomic number of an element?
The number of protons in the nucleus of an atom
What do all atoms of an element have in common?
The same atomic number
Define “isotope”
Atoms of the same element containing different mass numbers (different number of neutrons)
Why do isotopes have the same reactivity and chemical properties?
They have the same configuration of electrons
Why do isotopes have different physical properties e.g rate of diffusion?
Different atomic mass
Define “relative atomic mass”
The average mass of an atom of an element relative to 1/12 the mass of one atom of carbon-12
How do most elements exist naturally?
As a mixture of isotopes
What is relative atomic mass an average of?
Relative isotopic mass, taking isotopic abundance into account
What determines the chemical properties of an element?
The number and arrangement of electrons
What often determines the physical properties of an element?
The mass of the atom
