<p>Bond dissociation energy of XY,&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>X</mi><mn>2</mn></msub><mo>&#160;</mo><mi>a</mi><mi>n</mi><mi>d</mi><mo>&#160;</mo><msub><mi>Y</mi><mn>2</mn></msub></math>&nbsp;(all diatomic molecules) are in the ratio 1 : 1 : 0.5 and&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML" class="wrs_chemistry"><mo>&#8710;</mo><msub><mi mathvariant="normal">H</mi><mi mathvariant="normal">f</mi></msub></math>&nbsp;of XY is -200 kJ&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><mi>m</mi><mi>o</mi><msup><mi>l</mi><mrow><mo>-</mo><mn>1</mn></mrow></msup></math>. The bond dissociation energy of&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>X</mi><mn>2</mn></msub></math>&nbsp;will be</p>