What is the Atomic Number ALWAYS equal to?
The number of protons
Atomic masses are usually expressed as averages due to the existence of what phenomenon?
isotopes
Where are electrons located?
Electron orbital/ cloud
Neutrons have what kind of charge?
They have no charge, they are neutral
A cation of rubidium has a charge of +1. How many protons and electrons does it have?
37protons
36 electrons
The elements on the modern periodic table are always arranged in order of increasing?
atomic number
An ion of oxygen has a charge of -2. How many protons and electrons does it have?
8 protons
10 electrons
Which particle is most directly involved in bonding?
electron
What happens when an element gains an electron?
Does it become bigger or smaller?
More positive or more negative?
What is the exact mass of an electron?
1/1840 amu
How many neutrons are in a neutral atom of Lithium?
4
An isotope of oreoium weighs 40.00 amu and is found in 25% abundance. Another isotope weighs 42.00 amu and is found in 45% abundance. The last isotope weighs 45.00 amu and is found in 30% abundance. What is the average atomic mass?
42.4 amu