Answer:
- Metals in the second group make bases of the form M(OH)₂
- A nitrogen with three groups and a lone pair is a base since it can accept a proton.
Step-by-step explanation:
The answer choices are:
- Metals in the second group make bases of the form M(OH)₂
- Ammonium is an example of a "Nitrogen with 3 groups" base
- Metals in the first group make bases of the form M(OH)₂
- A nitrogen with three groups and a lone pair is a base since it can accept a proton
- HNO₃ has N as the central atom so it is a base
Solution
1. Metals in the second group make bases of the form M(OH)₂
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.
2. Ammonium is an example of a "Nitrogen with 3 groups" base
FALSE
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.
3. Metals in the first group make bases of the form M(OH)₂
FALSE
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.
4. A nitrogen with three groups and a lone pair is a base since it can accept a proton
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.
5. HNO₃ has N as the central atom so it is a base
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.