Question | Answer |
What group of elements has one valence electron in each atom and has low density? | Alkali Metals |
Lanthanides and Actinides are part of what group? | Transition Metals |
What group includes Calcium, Radium, has higher densities than alkali metals, and some of its elements are used in chalk and airplanes? | Alkaline-Earth Metals |
What group contains Gallium, has one metalloid and four metals, and are all solid at room temperature? | Boron Group |
What group has one nonmetal, two metalloids, two metals, and are all solids at room temperature? Elements, such as Tin, are used in cans. | Carbon Group |
What group has elements used for fertilizer, reactivity varies, and has five valence electrons? | Nitrogen Group |
What group has six valence electrons, three nonmetals, one metalloid, and one metal? One element is also used greatly in chemical industry, and another is very abundant in the air? | Oxygen Group |
What group is completely nonmetal and is VERY reactive? These elements combine with metals to create salts. | Halogens |
This group is completely nonmetal and are unreactive. An element includes Krypton. These elements are odorless. | Noble Gases |
This group contains a nonmetal that is very reactive. It is a gas at room temperature and has low density. | Hydrogen group |
This group includes Antimony and has five valence electrons. | Nitrogen Group |
This group includes Beryllium and are all silver in color. They have higher densities than alkali-metals. | Alkaline Earth Metals |
This group includes one metalloid and four metals and has three valence electrons. | Boron group |
This group includes Ununquadium and are all solids at room temperature. Another element is Germanium, which is used in computer chips. | Carbon Group |
Sodium and Potassium are in this group. | Alkali Metals |
This group of elements have luster, are good conductors, and all have high melting points and densities (except for Mercury). | Transition Metals |
Helium is in this group, and is an exception to the number of valence electrons. All have eight except for helium, which has two. | Noble Gases |
This person eventually arranged the elements in order of increasing mass. | Dmitri Mendeleev |
This plus number of neutrons equals the atomic number. | Number of Protons |
Are electrons included in the atomic mass? | No. |
This determines an element's identity (two answers). | Atomic number and Symbol. |
Are isotopes related to neutrons, electrons, or protons? | neutrons |
In an isotope, the number of _____ need to be equal to the number of protons or more. | neutrons. |
An positively charged ion has more or less electrons than protons. | less. |
Name the four forces in an atom. | gravitational, electromagnetic, strong, and weak. |
The ____ force plays an important role in radioactive atoms | weak |
Electromagnetic forces keep ___ and ___ together. | protons and electrons. |
The strong force keeps particles of ___ charges together. | Similar, like. |
Who discovered the number of protons? What year? | Henry Moseley; in 1914 |
Explain the Periodic Law. | Periodic Law states that the repeating chemical and physical properties of elements change PERIODICALLY with the elements' atomic numbers. |
Explain the three types of elements. | Metals: luster, good conductors, ductile, malleable.
Nonmetals: opposite of metals; dull, brittle.
Metalloids: Semi-conductors. |
What are rows called? Columns? | Rows: Periods.
Columns: groups, families. |
What do electrons rotate the nucleus on or in? | Electron clouds, energy levels, shells. |
Are all letters in a symbol capital? | No. Only the first is. |
When did the discoverer of the periodic table discover it? | 1869 |
Where do we find the three types of elements on the periodic table? | Metals: Left of zigzag
Metalloids: border of zigzag
Nonmetals: Right of zigzag |
What changes gradually as you move from left to right? | Conductivity and Reactivity. |
Elements in the same group often have similar ___ and ___ properties. | physical and chemical. |
Why are the properties in groups similar? | Same number of electrons in valence shell. |
Elements will give, share, or take electrons to complete a set of electrons. What are elements such as these described as? | Reactive. |