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C17 - Atoms and P.T.
Chapter 17 – Properties of Atoms and the Periodic Table
Question | Answer |
---|---|
The smallest piece of matter that still retains the properties of the element | Atom |
Number on the periodic table that represents the number of protons in an atom | Atomic Number |
Number on the periodic table that is the weighted average mass of the mixture of isotopes that exists naturally for an element | Average Atomic Mass |
Showed through light spectroscopy that electrons existed in specific energy levels in 1913 | Bohr |
Father of modern atomic theory – showed with experiments in 1800 that all elements had atoms as their smallest particles | Dalton |
Ancient Greek who first said all matter was made of small indivisible particles called “atomos” | Democritus |
Region outside of the nucleus where the electrons are found | Electron Cloud |
Current atomic model with electrons not as particles in orbits, but wave-particles in areas of probability | Electron Cloud Model |
Negatively charged particles in an atom | Electrons |
Vertical column in the periodic table | Group or Family |
Atoms of the same element that have different numbers of neutrons | Isotopes |
The sum of the number of protons plus neutrons in the nucleus | Mass Number |
Put together the first periodic table based on increasing atomic mass | Mendeleev |
Elements that are found on the left side of the periodic table (left of zigzag dividing line) | Metals |
Elements that have properties of both metals and nonmetals | Metalloids |
Changed the periodic table to be in order by atomic number | Moseley |
Elements found to the right of the zigzag dividing line in the periodic table | Nonmetals |
Neutral particles in the nucleus of an atom | Neutrons |
The center of the atom containing protons and neutrons | Nucleus |
Horizontal row in the periodic table | Period |
Table of elements arranged according to repeated changes in properties | Periodic Table |
Positively charged particles in an atom | Protons |
Smallest known particle that makes up protons and neutrons | Quarks |
Discovered the positive nucleus at the center of atoms with gold foil experiment in 1911 | Rutherford |
Discovered electrons with cathode ray tube experiments in 1904 | Thompson |
Name for elements found in the middle part of the periodic table (families 3-12) | Transition elements |
Each energy level of an atom can hold a maximum number of what? | electrons |
The filling order for electrons in a Bohr diagram is | 2,8,8,2 |
What do the dots in a Lewis Electron Dot diagrams represent? | electrons in the outer level |
What does the chemical symbol represent? | the name of an element |
The mass number of any element equals what? | The protons + the neutrons |
To what family do the elements in group 17 belong? | halogen family |
How are most synthetic elements classed? | rare earth metals |
What states of matter did we indicate on our periodic tables? | Solid, liquid, gas |
In what state of matter are most elements at room temperature? | solid |
Where is the atomic number found? | At the top of the element box |
What unit is used to measure the size (diameter) of an atom? | Angstrom |
What do we use to describe or show what something very large or small “looks like?” | We use indirect observation to create models |
How did Mendeleev arrange the first periodic table? (two things) | By increasing mass and similar properties |
Why do different metals produce different colors when burned? | Electrons are “excited” by added energy, and jump to another energy level. When they “fall back,” they release energy as light. The amount released determines the color seen. |
Elements in the same family share similar properties because they have | the same number of electrons in the outer energy level. |
Elements in Group/Family 1 have what kinds of properties? | They are soft metals and react to water (H20) |
How do you order elements from smallest to largest? | By increasing Atomic mass. (The lower they are on the periodic table, the heavier they are.) |
What will the atomic mass of the most common element of any element equal? | The atomic mass number (average atomic mass rounded) |
How do you indicate a specific isotope of an element? | By adding the mass number of that isotope (example: H-1, C-14) |
How do we show protons, neutrons and electrons on a Bohr diagram? | proton – p+; neutron – n°; electron – e- |