Mark the correct statements(s)
(1) Manganeses exhibits `+7` oxidation state
(2) Zinc forms coloured ions
(3) `[CoF_(6)]^(3-)` is diamagnetic
(4) Sc forms `+4` oxidation state
(5) Zn exhibits only `+2` oxidation state

Options

A. (i) and (ii)
B. (ii) and (iv)
C. (iii) and (iv)
D. (i) and (v)

Answer

To solve the question, we need to evaluate each of the provided statements about the elements and their oxidation states or properties. Let's analyze each statement step by step:

### Step 1: Evaluate Statement 1
**Statement:** Manganese exhibits +7 oxidation state.
**Analysis:** Manganese (Mn) has an atomic number of 25 and an electronic configuration of [Ar] 3d^5 4s^2. Manganese can lose up to 7 electrons (2 from 4s and 5 from 3d) to achieve a +7 oxidation state. An example of this is the permanganate ion (MnO4^-), where manganese is in the +7 oxidation state.
**Conclusion:** This statement is **correct**.

### Step 2: Evaluate Statement 2
**Statement:** Zinc forms coloured ions.
**Analysis:** Zinc (Zn) has an atomic number of 30 and an electronic configuration of [Ar] 3d^10 4s^2. In its common oxidation state of +2, it loses the two 4s electrons, resulting in a 3d^10 configuration. Since all d-orbitals are filled, there are no unpaired electrons, and thus zinc ions are colorless.
**Conclusion:** This statement is **incorrect**.

### Step 3: Evaluate Statement 3
**Statement:** [CoF6]^(3-) is diamagnetic.
**Analysis:** Cobalt (Co) has an atomic number of 27 and an electronic configuration of [Ar] 3d^7 4s^2. In the +3 oxidation state, cobalt has an electronic configuration of 3d^6. The fluoride ion (F^-) is a weak field ligand, which means it does not cause pairing of electrons in the d-orbitals. Therefore, in [CoF6]^(3-), there will be unpaired electrons, making it paramagnetic.
**Conclusion:** This statement is **incorrect**.

### Step 4: Evaluate Statement 4
**Statement:** Scandium forms +4 oxidation state.
**Analysis:** Scandium (Sc) has an atomic number of 21 and an electronic configuration of [Ar] 3d^1 4s^2. The common oxidation states of scandium are +2 and +3, as it can lose the two 4s electrons and the single 3d electron. It does not typically exhibit a +4 oxidation state.
**Conclusion:** This statement is **incorrect**.

### Step 5: Evaluate Statement 5
**Statement:** Zn exhibits only +2 oxidation state.
**Analysis:** As previously mentioned, zinc typically loses its two 4s electrons to form a +2 oxidation state. It does not exhibit any other oxidation states because the 3d electrons are tightly held due to effective nuclear charge.
**Conclusion:** This statement is **correct**.

### Final Answer
The correct statements are **1 and 5**.