Which of the following is NOT a carbon containing compound? Carbon Dioxide (CO2) Calcium Carbonate (CaCO3) Water (H2O) Methane (CH4)

The correct answer is Water $(H2O)$.<br /><br />Explanation:<br />Carbon-containing compounds are compounds that contain the element carbon. Among the options provided:<br /><br />1. Carbon Dioxide $(CO2)$ is a carbon-containing compound, as it contains one carbon atom bonded to two oxygen atoms.<br />2. Calcium Carbonate $(CaCO3)$ is a carbon-containing compound, as it contains one carbonate ion $(CO3^{2-})$, which contains one carbon atom bonded to three oxygen atoms.<br />3. Water $(H2O)$ is not a carbon-containing compound, as it only contains hydrogen and oxygen atoms.<br />4. Methane $(CH4)$ is a carbon-containing compound, as it contains one carbon atom bonded to four hydrogen atoms.<br /><br />Therefore, the compound that is NOT a carbon-containing compound is Water $(H2O)$.