Quiz #2 Flashcards
What is the mass of a proton?
1 AMU or 1.66 x 10^-27
What is the mass of an electron?
Mass is so small it is (mostly) irrelevant
What is the mass of a neutron?
1 AMU or 1.66 x 10^-27
Atomic number (Z)
Number of protons.
Is the identifying number of the atom
Cation
positive
Anion
negative
Compounds
More than one kind of atom in a fixed ratio by mass
Molecules
groups of atoms chemically bonded together into a discrete unit by covalent bonds.
Net neutral charge.
Ionic compounds
contain both positive and negatively charged ions with no identifiable units.
Attracted by charges and are not molecules
Can a substance be both a molecule and an element?
Yes; oxygen for example
Physical change
No change in the chemical makeup.
Ex. melting ice
Chemical change
Always makes a chemically different substance
Intensive physical property
Integral to the material, regardless of amount
Extensive physical property
Depends on sample size.
Ex: volume.
Substances
Pure materials that can’t be physically seperated into simpler components.
Mixtures
2 or more pure substances.
Can be physically separated
What is the only element that does not contain a neutron?
Hydrogen