(i) `P+C("carbon")+Cl_(2) to Q+CO uaarr`
(ii) `Q+H_(2)O to R+HCl`
(iii) `BN+H_(2)O to R+NH_(3) uarr`
(iv) `Q+LiAlH_(4) to S+LiCl+AlCl_(3)`
(v) `S+H_(2) to R+H_(2) uarr`
(vi) `S+NaH to T`
(P,Q,R,S annd T do not represent their chemical symbols)
Q. Compound Q has:
(I) zero dipole moment.
(II) a planar trigonal structure
(III) an electron deficient compound
(IV) a lewis base
Chose the correct code:

Options

A. I,IV
B. I,II,IV
C. I,II,III
D. I,II,III,IV

Explanation

To solve the problem, we will analyze the given reactions step by step and determine the properties of compound Q, which is identified as BCl3 (boron trichloride).

### Step-by-Step Solution:

1. **Identify Compound P**:
- The first reaction is \( P + C + Cl_2 \rightarrow Q + CO \).
- From the video, we learn that \( P \) is \( B_2O_3 \) (boron trioxide).

2. **Identify Compound Q**:
- The reaction produces \( Q \) which is identified as \( BCl_3 \) (boron trichloride).

3. **Analyze Compound Q (BCl3)**:
- **(I) Zero Dipole Moment**:
- \( BCl_3 \) has a symmetrical trigonal planar structure with bond angles of 120°. The three B-Cl bonds are equal and symmetrically arranged, which results in the cancellation of dipole moments. Therefore, \( BCl_3 \) has a zero dipole moment.

- **(II) Planar Trigonal Structure**:
- The molecular geometry of \( BCl_3 \) is trigonal planar due to the three bonding pairs of electrons around the boron atom, with no lone pairs. This confirms that it has a planar trigonal structure.

- **(III) Electron Deficient Compound**:
- Boron has three valence electrons and forms three bonds with chlorine. However, it does not complete its octet (it has only 6 electrons around it). Thus, \( BCl_3 \) is considered an electron-deficient compound.

- **(IV) Lewis Base**:
- A Lewis base is defined as a species that can donate an electron pair. \( BCl_3 \) is not a Lewis base; rather, it acts as a Lewis acid because it can accept an electron pair due to its electron deficiency.

4. **Conclusion**:
- Based on the analysis, we can summarize the properties of compound Q (BCl3):
- (I) Zero dipole moment: **True**
- (II) Planar trigonal structure: **True**
- (III) Electron deficient compound: **True**
- (IV) Lewis base: **False**

5. **Correct Code**:
- The correct properties of compound Q are (I), (II), and (III). Therefore, the correct code is **3** (which denotes the first three statements).