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Stegall-Chem(201)#5
Atomic Structure
Question | Answer |
---|---|
How are elements abbreviated in chemical shorthand? | by a Symbol. One or two letter. The first letter is always a capital. If there is a second letter it is always lower case. |
What is an Atom? | The basic building block of all matter. |
What is an element? | A substance that contains only one type of Atom. A pure substance. |
What are the three particles in an Atom? | Protons, Neutrons & electrons. |
What is the electrical charge of a Proton? | Positive (+) |
What is the electrical charge of a neutron? | Neutral (o) |
What is the electrical charge of an electron? | Negative (-) |
What is the nucleus of an atom? | The center. The part of the atom with the most mass. |
What particles are in the nucleus of an atom? | Protons & Neutrons. |
What is the meaning of the Atomic Number? | Atomic Number = # of Protons. |
What is the meaning of the Atomic Mas #? | The Atomic Mass number = # of Protons + # of Neutrons. |
On the Periodic Table where can you find the Atomic Number? | The large number at the top of each square. |
On the Periodic Table where can you find the Atomic Mass number? | The Atomic Mass # in the decimal number at the bottom of each square. |
Where are the electrons of an atom located? | Outside of the nucleus in an electron cloud. |
Which atomic particle determines the properties of an element? | Electrons |
How much mass do the atomic particles have? | Protons & Neutrons contain most of the mass of the atom. The electrons are so small we cannot measure their mass. Electron mass is counted as zero. |
What is an Isotope? | An atom that has a different from normal # of neutrons. |
What is an Ion? | An atom with an electric charge. |
How does an atom gain an electrical charge? | It gains or loses one or more electrons. |
How does a normal atom maintain a total neutral charge? | Equal numbers of Protons (+) and Electrons (-). |
From the Periodic Table, how do you find the # of Neutrons in an atom? | # of Neutrons = Atomic Mass - Atomic Number. or Atomic Mass - # of Protons. |
Do we know the exact location of electrons in the electron cloud? | No. The exact location of electrons cannot be known for certain. We can only predict the approximate & probably location of the electrons in various shell energy levels, from closest to the nucleus to further and further from the nucleus. |
How do you find the # of Protons on the Periodic Table? | The Atomic Number is the large # at the top of each square. |
How do you find the Atomic Mass on the Periodic Table? | The Atomic Mass is the decimal number at the bottom of each square. |
What is a Shell Energy Level? | The approximate location of electrons in the electron cloud surrounding the atomic nucleus. |