What is the oxidation number of the chlorine atom in the chlorinium ion, Cl1+? 2. What is the oxidation number of the chlorine atom in aluminum trichloride, AlCl3? 3. What is the oxidation number of the chlorine atom in dichlorine, Cl2? 4. What is the oxidation number of the chlorine atom in the gas phase, Cl(g)? 5. What is the oxidation number of the chlorine atom in dichlorine heptaoxide, Cl2O7? 6. What is the oxidation number of the chlorine atom in hydrogen chloride, HCl? 7. What is the oxidation number of the chlorine atom in chlorine dioxide, ClO2? 8. What is the oxidation number of the chlorine atom in Cl2O?
The Correct Answer and Explanation is:
- Oxidation number of chlorine in chlorinium ion, Cl⁺:
The chlorinium ion, Cl⁺, has a +1 charge. Since chlorine is more electronegative, it would take on a positive oxidation state to balance the charge. Hence, the oxidation number of chlorine in this ion is +1. - Oxidation number of chlorine in aluminum trichloride, AlCl₃:
In AlCl₃, aluminum (Al) typically has an oxidation number of +3 (as it’s in Group 13). Since the molecule is neutral overall, and there are three chlorine atoms, the total oxidation number of the chlorines must balance the +3 from aluminum. Each chlorine atom thus has an oxidation number of -1. - Oxidation number of chlorine in dichlorine, Cl₂:
In its elemental form, chlorine in Cl₂ is not combined with any other element, and its oxidation number is 0. This is because, in any pure elemental substance, the oxidation number is always 0. - Oxidation number of chlorine in the gas phase, Cl(g):
When chlorine is in its atomic form as a gas (Cl(g)), it is not bonded to any other atoms, and like any elemental atom, its oxidation number is 0. - Oxidation number of chlorine in dichlorine heptaoxide, Cl₂O₇:
In dichlorine heptaoxide, the oxygen atoms are typically assigned an oxidation number of -2 (since oxygen is usually -2). Since there are seven oxygen atoms, the total oxidation number for oxygen is -14. To balance this, the two chlorine atoms must contribute +14. Dividing by two, each chlorine atom has an oxidation number of +7. - Oxidation number of chlorine in hydrogen chloride, HCl:
In HCl, hydrogen typically has an oxidation number of +1. To balance this, the chlorine must have an oxidation number of -1, making the molecule neutral overall. - Oxidation number of chlorine in chlorine dioxide, ClO₂:
In ClO₂, oxygen is typically assigned an oxidation number of -2. Since there are two oxygen atoms, the total oxidation number for oxygen is -4. The molecule is neutral, so the chlorine atom must have an oxidation number of +4 to balance the -4 from oxygen. - Oxidation number of chlorine in dichlorine monoxide, Cl₂O:
In Cl₂O, the oxygen has an oxidation number of -2. Since there is only one oxygen atom, the total oxidation number for oxygen is -2. To balance this, the two chlorine atoms must collectively have an oxidation number of +2. Dividing by two, each chlorine atom has an oxidation number of +1.
Summary of oxidation numbers:
- Chlorinium ion (Cl⁺) = +1
- Aluminum trichloride (AlCl₃) = -1
- Dichlorine (Cl₂) = 0
- Chlorine gas (Cl(g)) = 0
- Dichlorine heptaoxide (Cl₂O₇) = +7
- Hydrogen chloride (HCl) = -1
- Chlorine dioxide (ClO₂) = +4
- Dichlorine monoxide (Cl₂O) = +1
