The compound which contains both ionic and covalent bonds is

Options

A. `CH_(4)`
B. `H_(2)`
C. `KCN`
D. `KCI`

Explanation

To solve the question of which compound contains both ionic and covalent bonds, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Ionic Bonds:**
- Ionic bonds are formed between metals and non-metals through the complete transfer of electrons. This results in the formation of positively charged cations and negatively charged anions, which are held together by electrostatic forces.

2. **Understanding Covalent Bonds:**
- Covalent bonds occur between non-metals and involve the mutual sharing of electrons. This type of bond results in the formation of molecules where the atoms share their valence electrons.

3. **Analyzing the Options:**
- **Option A: Methane (CH4)**
- Methane consists of one carbon atom and four hydrogen atoms. The bonds formed here are covalent bonds due to the sharing of electrons between carbon and hydrogen.
- **Conclusion:** CH4 has only covalent bonds.

- **Option B: Hydrogen Gas (H2)**
- Hydrogen gas consists of two hydrogen atoms that share their electrons to form a covalent bond.
- **Conclusion:** H2 has only covalent bonds.

- **Option C: Potassium Chloride (KCl)**
- KCl is formed from potassium (a metal) and chlorine (a non-metal). Potassium donates one electron to chlorine, resulting in the formation of K+ and Cl- ions, which are held together by ionic bonds.
- **Conclusion:** KCl has only ionic bonds.

- **Option D: Potassium Cyanide (KCN)**
- KCN consists of potassium (K), which forms a K+ ion, and the cyanide ion (CN-). The bond between K+ and CN- is ionic due to the transfer of an electron from potassium to the cyanide ion.
- Within the cyanide ion, there is a triple bond between carbon and nitrogen (C≡N), which is a covalent bond due to the sharing of electrons.
- **Conclusion:** KCN has both ionic (K+ and CN-) and covalent (C≡N) bonds.

4. **Final Answer:**
- The compound which contains both ionic and covalent bonds is **Potassium Cyanide (KCN)**.