1. Name the three particles of the atom and their respective charges are: a.b.
2. The number of protons in one atom of an element determines the atom’s
, and the number of electrons determines
of an element.
3. The atomic number tells you the number of in one atom of an element. It also tells you the number of in a neutral atom of that element. The atomic number gives the “identity “ of an element as well as its location on the Periodic Table. No two different elements will have the atomic number.
4. The of an element is the average mass of an element ’s naturally occurring atoms, or isotopes, taking into account the of each isotope.
5. The of an element is the total number of protons and neutrons in the of the atom.
6. The mass number is used to calculate the number of in one atom of an element. In order to calculate the number of neutrons you must subtract the from the .
7. Give the symbol and number of protons in one atom of:
8. Give the symbol and number of electrons in a neutral atom of:
9. Give the isotope symbol and number of neutrons in one atom of the following elements. Show your calculations.
Barium – 138 Sulfur – 32
Carbon – 12 Hydrogen – 1
Fluorine – 19 Magnesium – 24
Silicon - 28 Mercury – 202
10. Name the element which has the following numbers of particles. Be specific. (Include charges and mass numbers where possible.)
26 electrons, 29 neutrons, 26 protons
53 protons, 74 neutrons
2 electrons (neutral atom)
86 electrons, 125 neutrons, 82 protons (charged atom)
11. If you know ONLY the following information can you always determine what the element is? (Yes/No). number of protons
number of neutrons
number of electrons in a neutral atom
number of electrons