Answer: The bond between boron and hydrogen in boron trihydride is covalent bond.
Step-by-step explanation:
The type of bonding between the atoms forming a compound is determined by using the electronegativity difference between the atoms. According to the pauling's electronegativity rule:
- If
, then the bond is non-polar. - If
, then the bond will be covalent. - If
, then the bond will be ionic.
We are given:
Electronegativity for boron = 2.0
Electronegativity for hydrogen = 2.1
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As,
is less than 1.7 and not equal to 0. Hence, the bond between boron and hydrogen is covalent bond.