Lithium borohydride crystallizes in an orthorhombic system with 4 molecule per unit cell. The unit cell dimensions are `a=6.8Å,b=4.4Å` and `c=7.2Å`. If the molar mass is `21.76`, calculate density of crystal.

Options

A. `0.6708 g cm^(-3) `
B. `1.6708 g cm^(-2)`
C. `2.6708 g cm^(-2)`
D. None of these

Explanation

To calculate the density of lithium borohydride (LiBH4) crystallizing in an orthorhombic system, we can follow these steps:

### Step 1: Identify the given data
- Molar mass (M) = 21.76 g/mol
- Number of molecules per unit cell (Z) = 4
- Unit cell dimensions:
- a = 6.8 Å
- b = 4.4 Å
...