Question
- How is diborane prepared in the laboratory? Draw its structure.
- Explain why $\mathrm{CO}_2$ is a gas whereas $\mathrm{SiO}_2$ is a solid.
✓
Answer
- $2\text{naBH}_4+\text{I}_2\xrightarrow{\ \ \ \ \ \ \ }\text{B}_2\text{H}_6+2\text{NaI}+\text{H}_2$
- $\mathrm{CO}_2$ exists as descrete molecules which are held together by weak van der Waals' forces of attraction whereas $\mathrm{SiO}_2$ is three dimensional covalent solid.
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