<em>B</em><em> </em><em>i</em><em>s</em><em> </em><em>r</em><em>i</em><em>g</em><em>h</em><em>t</em><em> </em><em>a</em><em>n</em><em>s</em><em>w</em><em>e</em><em>r</em><em> </em><em>i</em><em>t</em><em>h</em><em>i</em><em>n</em><em>k</em><em> </em><em>b</em><em>r</em><em>o</em><em>/</em><em>s</em><em>i</em><em>s</em>
Answer:
D
Explanation: A precipitation reaction is a type of chemical reaction in which two soluble salts in aqueous solution combine and one of the products is an insoluble salt called a precipitate.
Answer: -134 kJ
Explanation:
The balanced chemical reaction is,
The expression for enthalpy change is,
![\Delta H=\sum [n\times \Delta H_f(product)]-\sum [n\times \Delta H_f(reactant)]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H_f%28product%29%5D-%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H_f%28reactant%29%5D)
![\Delta H=[(n_{HNO_3}\times \Delta H_{HNO_3})+(n_{NO}\times \Delta H_{NO})]-[(n_{H_2O}\times \Delta H_{H_2O})+(n_{NO_2}\times \Delta H_{NO_2})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%28n_%7BHNO_3%7D%5Ctimes%20%5CDelta%20H_%7BHNO_3%7D%29%2B%28n_%7BNO%7D%5Ctimes%20%5CDelta%20H_%7BNO%7D%29%5D-%5B%28n_%7BH_2O%7D%5Ctimes%20%5CDelta%20H_%7BH_2O%7D%29%2B%28n_%7BNO_2%7D%5Ctimes%20%5CDelta%20H_%7BNO_2%7D%29%5D)
where,
n = number of moles
Now put all the given values in this expression, we get
![\Delta H=[(2\times -207)+(1\times 90)]-[(1\times -286)+(3\times 32)]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%282%5Ctimes%20-207%29%2B%281%5Ctimes%2090%29%5D-%5B%281%5Ctimes%20-286%29%2B%283%5Ctimes%2032%29%5D)
Therefore, the enthalpy change for this reaction is, -134 kJ
