Hydrogen, Alkali Metals, and Alkaline Earth Metals (8.3.1) Flashcards
• The periodic table was constructed by placing elements in order by molecular weight and arranging them in columns by chemical reactivity.
• The periodic table was constructed by placing elements in order by molecular weight and arranging them in columns by chemical reactivity.
• The periodic table can be broken down into metals, nonmetals, and metalloids
• The periodic table can be broken down into metals, nonmetals, and metalloids
• Elements within the same group have similar reactivity.
• Elements within the same group have similar reactivity.
Elements were placed in order by molecular weight.
Elements with similar chemical reactivity were arranged in families (or groups) by columns.
By putting elements with similar chemical reactivity into
groups, it was possible to hypothesize where there may
have been “missing” elements which had not yet been
discovered.
Elements were placed in order by molecular weight.
Elements with similar chemical reactivity were arranged in families (or groups) by columns.
By putting elements with similar chemical reactivity into
groups, it was possible to hypothesize where there may
have been “missing” elements which had not yet been
discovered.
Metals are to the left and the bottom of the periodic table
Nonmetals are located in the top right corner.
Metalloids are in between metals and nonmetals.
Metals are to the left and the bottom of the periodic table
Nonmetals are located in the top right corner.
Metalloids are in between metals and nonmetals.
Hydrogen can react to gain or to lose an electron.
Alkali metals tend to form monovalent cations. Alkali
metals have the tendency to lose their valence electron.
When alkali metals react with water they tend to form the
metal cation and OH–, resulting in a basic solution.
Alkaline earth metals tend to form divalent cations.
Alkaline earth metals react with water in a 1:1 ratio to
give OH–. When the alkaline earths react with water the
resulting solution is basic (or alkaline).
Hydrogen can react to gain or to lose an electron.
Alkali metals tend to form monovalent cations. Alkali
metals have the tendency to lose their valence electron.
When alkali metals react with water they tend to form the
metal cation and OH–, resulting in a basic solution.
Alkaline earth metals tend to form divalent cations.
Alkaline earth metals react with water in a 1:1 ratio to
give OH–. When the alkaline earths react with water the
resulting solution is basic (or alkaline).
In the following chemical reaction, what is oxidized?
2Li + 2H2O → H2(g) + 2Li+ (aq) + 2OH − (aq)
Li (A)
The oxidation number for lithium (Li) increases from 0 (elemental lithium) to +1. Lithium gives up an electron and is thus oxidized.
Which of the following chemical elements has properties that are most similar to selenium?
Sulfur (C)
Sulfur and selenium are found in the same group in the periodic table. Each group in the periodic table is made up of elements that have similar properties.
Which of the following properties is shared by the alkali metals and the alkaline earth metals?
They are not found in their elemental state in nature. (D)
The alkali metals and alkaline earth metals are both metals, a very reactive group, and they readily lose one or two electrons. Because of these properties, they are not found in their elemental states. If they were, they would quickly react with either water or oxygen, both of which are very common in nature.
Which of the following groups in the periodic table is made up entirely of metals?
Group 2 (A)
Group 2 is the alkaline earth metals, beryllium, magnesium, calcium, strontium, barium, and radium. Of the listed groups, it is the only one in which all elements in the column are metals.
Which of the following pairs of elements will react in a similar manner?
Na and K (D)
Which of the following describes the ionization energy trend through the periodic table?
Ionization energy increases from left to right and decreases from top to bottom within a column. (A)
Electrons that are farther away from the center of an atom are more easily removed than electrons that are closer to the center. Moving across the periodic table from left to right, the ionization energy increases because the increasing nucleus size increases the pull by the nucleus on the outer electrons. Moving down a column in the periodic table, the distance between the outer electrons increases so the pull by the nucleus on the electrons decreases.
In a compound, what is the oxidation number of magnesium?
2+ (D)
Magnesium is an alkaline earth metal and it easily loses 2 electrons from its outer electron shell. Because it loses two electrons, it has an oxidation number of 2+.
What is the name of the group of elements that react with oxygen in a 1:1 ratio and have a 2+ oxidation state?
Alkaline earth metals (C)
The alkaline earth metals are located in the second group of the periodic table. They have 2 electrons in s orbitals in their outer shell. Because there are only 2 electrons in their outer shell, they can lose these to have an oxidation state of 2+. Because of their 2+ oxidation state, they react with oxygen (−2 charge) in a 1:1 ratio.
Which of the following pairs of metals and nonmetals would combine in a 1:1 ratio in a chemical reaction?
Rubidium and Iodine (C)
Rubidium is an alkali metal in group 1 of the periodic table. The alkali metals form ions with an oxidation state of 1+. Iodine is a halogen in group 7 of the periodic table and forms ions with an oxidation state of 1−. This metal and nonmetal pair react with a ratio of 1:1.
