Answer:
- <u>Metals in the second group make bases of the form M(OH)₂</u>
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- <u>A nitrogen with three groups and a lone pair is a base since it can accept a proton. </u>
Explanation:
The answer choices are:
- <em>Metals in the second group make bases of the form M(OH)₂</em>
- <em> Ammonium is an example of a "Nitrogen with 3 groups" base </em>
- <em>Metals in the first group make bases of the form M(OH)₂ </em>
- <em>A nitrogen with three groups and a lone pair is a base since it can accept a proton </em>
- <em>HNO₃ has N as the central atom so it is a base</em>
<h2>Solution</h2>
<em>1. Metals in the second group make bases of the form M(OH)₂</em>
TRUE
The metals in the second group have two valence electrons, thus they can lose them to form cation with +2 oxidation state and bond with two (OH)⁻ groups, forming bases with the general formula M(OH)₂. For instance, Mg(OH)₂ and Ca(OH)₂.
<em>2. Ammonium is an example of a "Nitrogen with 3 groups" base </em>
FALSE
<em>Ammonium is NH₃. The "nitrogen with 3 groups" base are the compounds where the three hidrogens are replaced with R-groups, where R are alkyl groups.</em>
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<em>3. Metals in the first group make bases of the form M(OH)₂ </em>
<em />
FALSE
<em />
Since metals in first group of the periodic table have one valence electrons they make bases of the form MOH. For instance, NaOH and KOH.
<em>4. A nitrogen with three groups and a lone pair is a base since it can accept a proton </em>
<em />
TRUE
Since nitrogen has five valence electrons, when it bonds to three groups, it will retain a lone pair of electrons which make it a base under the Lewis concept and can accept a proton.
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<em>5. HNO₃ has N as the central atom so it is a base</em>
FALSE
It is true that N is the central atom in HNO₃ but this compound is an acid as it releases a proton in aqueous solution.