The IUPAC name of `[Co(H_2NCH_2CH_2NH_2)_2 (NO_2)NO_5` is bis(enthane-1,2-diamine) dinitrito-N-cobalt(III) nitrate.It follows the following rules that.
(a)Cation is named first followed by anion.
(b) Ligands are named in an alphabetical order before the name of the central atom/ion.
( c)Name of anionic ligands end in "o" (ex.chlorido) those of neutral (and if cation) ligands are the same except aqua for `H_2O`, ammine for `NH_3` etc.
(d)Prefixes mono,di,tri,etc.are used to indicate the number of individual ligand.When the name of the ligands include a numerical prefix, then terms bis, tris, tetrakis are used.
(e)Oxidation state of the metal is indicated by Roman numeral in parenthesis.
(f) For cationic and neutral complexes, the metal is named same as the element and for anionic complex, the name of metal ends with suffix-ate.For some metals, the Latin names are used in the complex anions , e.g., ferrate for Fe, argentate for silver etc.
The correct IUPAC name of the coordination compound `[Pt(NH_3)_2Cl(NH_2CH_3)]` is :

Options

A. Diamminechlorido (methylamine ) plantinate (II) chloride
B. Chloridodiamine (methylamine)platinum (II) chloride
C. Diamminechlorido (methylamine)platinum (II) chloride
D. Diammine(methylamine) chloridoplatinum (II) chloride

Explanation

To determine the correct IUPAC name of the coordination compound `[Pt(NH_3)_2Cl(NH_2CH_3)]`, we will follow the rules outlined in the question step by step.

### Step-by-Step Solution:

1. **Identify the Ligands**:
- The complex contains three types of ligands:
- `NH3` (Ammonia) - This is a neutral ligand and is named as "ammine".
- `Cl` (Chloride) - This is an anionic ligand and is named as "chlorido".
- `NH2CH3` (Methylamine) - This is also a neutral ligand and is named as "methylamine".

2. **Count the Number of Each Ligand**:
- There are two `NH3` ligands, one `Cl` ligand, and one `NH2CH3` ligand.

3. **Alphabetical Order of Ligands**:
- When naming ligands, they must be listed in alphabetical order, ignoring any prefixes that indicate the number of ligands.
- The alphabetical order of the ligands is:
- "ammine" (from NH3)
- "chlorido" (from Cl)
- "methylamine" (from NH2CH3)

4. **Use of Prefixes**:
- Since there are two `NH3` ligands, we use the prefix "di" to indicate this: "diammine".
- The name for the ligands in order will be: "diammine", "chlorido", and "methylamine".

5. **Name the Central Metal Atom**:
- The central metal atom is platinum (Pt). Since it is a neutral complex, we use the name "platinum".

6. **Determine the Oxidation State of the Metal**:
- The overall charge of the complex is neutral. The oxidation state of platinum can be calculated as follows:
- Each `NH3` is neutral (0 charge).
- The `Cl` ligand contributes -1 charge.
- The `NH2CH3` is also neutral (0 charge).
- Therefore, the oxidation state of platinum must be +2 to balance the -1 charge from chloride.
- Thus, we indicate the oxidation state of platinum as (II).

7. **Combine All Parts**:
- Putting it all together, the name of the complex is:
- "diammine chlorido methylamine platinum(II)".

### Final Answer:
The correct IUPAC name of the coordination compound `[Pt(NH_3)_2Cl(NH_2CH_3)]` is **diammine chlorido methylamine platinum(II)**.