Answer: MgCO3, NH4OH and Al(NO3)3
Explanation:
The question requires us to write the chemical formula for the ionic compounds given.
An ionic compound is formed by a cation (positively charged) and anion (negatively charged) that combine themselves to form a compound with neutral charge. We can use the cross over rule to identify the chemical formula of an ionic compound: considering a generic cation A2+ and a generic anion B-, we would have:
The resultant ionic compound between A2+ and B- would be AB2.
Taking the cross over rule in consideration, we can determine the chemical formula for the compounds given:
- Magnesium carbonate: this compound is formed by the ions Mg2+ and (CO3)2-. Note that both cation and anion present charges with the same magnitude, thus the compound formed by these ions only need one of each:
[tex]\text{MgCO}_3[/tex]
- Ammonium hydroxide: this compound is formed by the ions (NH4)+ and OH-. Just like the previous compound, these ions present the same charge in value, thus the compound formed only needs one of each to achieve neutral charge:
[tex]NH_4OH[/tex]
- Aluminum nitrate: this compound is formed by the ions Al3+ and (NO3)-. In this case, three anions are necessary to balance the +3 charge of the cation:
[tex]Al(NO_3)_3[/tex]
We can apply the cross over rule to these compounds as it follows:
(note that when we have two coefficients that are the same, such as in Mg2(CO3)2, we can simplify them to the smallest coefficient: MgCO3)
