Ionic compound: Calcium carbonate What is the cation and anion? What is the correct formula for it? Does it have more than one positive ion? What kind of element is it and description? Does it react with other molecules? List the formula of one example.
The Correct Answer and Explanation is:
Calcium Carbonate (CaCO₃) is an ionic compound composed of two types of ions: a cation and an anion.
Cation:
- Calcium ion (Ca²⁺): The calcium ion is positively charged with a charge of +2. It is derived from calcium (Ca), an alkaline earth metal found in Group 2 of the periodic table.
Anion:
- Carbonate ion (CO₃²⁻): The carbonate ion is a polyatomic ion with a negative charge of -2. It consists of one carbon atom (C) covalently bonded to three oxygen atoms (O₃), and the overall charge of the ion is -2.
Formula:
- The correct formula for calcium carbonate is CaCO₃. This formula is balanced, meaning the two charges from the calcium ion (+2) and the carbonate ion (-2) cancel each other out, resulting in a neutral compound.
Does it have more than one positive ion?
- No, calcium carbonate does not have more than one positive ion. It only contains the Ca²⁺ ion as the cation. Calcium typically forms only a +2 charge in its compounds, so there’s no additional positive ion.
Type of Element:
- Calcium is a metal, specifically an alkaline earth metal from Group 2 of the periodic table. It is an essential element for life, particularly in bones and teeth.
- Carbon is a non-metal, a fundamental element that plays a key role in organic chemistry and living organisms.
- Oxygen is also a non-metal and one of the most abundant elements on Earth.
Reactivity:
- Calcium carbonate reacts with acids to form carbon dioxide gas, water, and a salt. A typical reaction would be when it reacts with hydrochloric acid (HCl): CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂
This reaction is commonly observed when limestone (which contains calcium carbonate) is exposed to acids.
Example Reaction Formula:
- A reaction of calcium carbonate with hydrochloric acid:
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂
This shows how calcium carbonate dissolves and releases carbon dioxide when reacting with an acid.
