REUSE

Nitric acid is the most important oxyacid formed y nitrogen .It is one of the major industial chemicl and is widely used. Nitric acid is manufactured by the catalytic oxidation of ammonia in what is known as OSTWALD PROCESS which can be represented by the sequenve of reactions shown below: 4NH_(3)(g) +5O_(2)(g) underset("Catalyst")overset(Pt//Rh)rarr 4NO(g)+6H_(2)O(g) " "...(i) 2NO(f) + O_(2)(g) overset(1120 K) rarr 2NO_(2)(g)" "...(ii) 3NO_(2)(g)+H_(2)O(l) rarr 2HNO_(3)(aq)+NO(g)" "...(iii) The aqueous nitric acid obtained by this method can be concentrated by distillation to ~ 68.5 % by weight . Further concentrated to 98% acid can be achieved by dehyration with concentrated sulphuric acid. 85 kg of NH_(3)(g) was heated with 320 kg oxygen in the first step and NHO_(3) is prepared according to the above reactions . If the above reactions . If the final solution has volume 500 L ,then molarity of HNO_(3) is : [Assume NO formed finally is not reused]

Read the passage given below and answer the question: Industrially widely applied esterification reactions are commonly catalysed using mineral liquid acids, such as sulphuric acid and p-toluenesulphonic acid. The catalytic activity of homogeneous catalysts is high. They suffer, however, from several drawbacks, such as their corrosive nature, the existence of side reactions, and the fact that the catalyst cannot be easily separated from the reaction mixture. The use of solid acid catalysts offers an alternative and has received a lot of attention in the past years. Solid acid catalysts are not corrosive and, coated onto a support, they can be easily reused. Examples of solid acid catalysts used in esterification reactions include ion-exchange resins, zeolites and superacids like sulphated zirconia and niobium acid. Ion-exchange resins are the most common heterogeneous catalysts used and have proven to be effective in liquid phase esterification and etherification reactions. Because of their selective adsorption of reactants and swelling nature, these resins not only catalyse the esterification reaction but also affect the equilibrium conversion. Shortcomings include insufficient thermal resistance, which limits the reaction temperature to 120^(@)C , preventing widespread use in industry. Zeolites, like Y, X, BEA, ZSM-5 and MCM 41 offer an interesting alternative and have proven to be efficient catalysts for esterification reactions. Zeolites have found wide application in oil refining, petrochemistry and in the production of fine chemicals. Their success is based on the possibility to prepare zeolites with strong Brønsted acidity that can be controlled within a certain range, combined with a good resistance to high reaction temperatures. In this study, the activity of various commercial available solid acid catalysts is assessed with respect to the esterification of acetic acid with butanol. The ion-exchange resins Amberlyst 15 and Smopex-101, the acid zeolites H-ZSM-5, H-MOR, H-BETA and H-USY, and the solid superacids sulphated zirconia and niobium acid are selected. Comparative esterification experiments have been carried out using the homogeneous catalysts sulphuric acid, p toluenesulphuric acid and a heteropolyacid (HPA). The weight-based activity of the heterogeneous catalysts tested is maximum for Smopex 101. The following table gives the activity of different catalysts in the esterification reaction between acetic acid and butanol at 75^(@)C . Here: k_(obs) : observed reaction rate constant ( m^(3) mol^(-1)s^(-1) ) kc catalysed reaction rate constant ( m^(3)mol^(-1) g_(cat)^(-1)s^(-1) ) Please note: k c = k obs/ amount (in g) (source: PETERS, T., BENES, N., HOLMEN, A., & KEURENTJES, J. (2006). Comparison of commercial solid acid catalysts for the esterification of acetic acid with butanol. Applied Catalysis A: General, 297(2), 182-188. doi:10.1016/j.apcata.2005.09.00) The weight-based activity of the heterogeneous catalysts tested decreases in the following order:

Read the passage given below and answer the question: Industrially widely applied esterification reactions are commonly catalysed using mineral liquid acids, such as sulphuric acid and p-toluenesulphonic acid. The catalytic activity of homogeneous catalysts is high. They suffer, however, from several drawbacks, such as their corrosive nature, the existence of side reactions, and the fact that the catalyst cannot be easily separated from the reaction mixture. The use of solid acid catalysts offers an alternative and has received a lot of attention in the past years. Solid acid catalysts are not corrosive and, coated onto a support, they can be easily reused. Examples of solid acid catalysts used in esterification reactions include ion-exchange resins, zeolites and superacids like sulphated zirconia and niobium acid. Ion-exchange resins are the most common heterogeneous catalysts used and have proven to be effective in liquid phase esterification and etherification reactions. Because of their selective adsorption of reactants and swelling nature, these resins not only catalyse the esterification reaction but also affect the equilibrium conversion. Shortcomings include insufficient thermal resistance, which limits the reaction temperature to 120^(@)C , preventing widespread use in industry. Zeolites, like Y, X, BEA, ZSM-5 and MCM 41 offer an interesting alternative and have proven to be efficient catalysts for esterification reactions. Zeolites have found wide application in oil refining, petrochemistry and in the production of fine chemicals. Their success is based on the possibility to prepare zeolites with strong Brønsted acidity that can be controlled within a certain range, combined with a good resistance to high reaction temperatures. In this study, the activity of various commercial available solid acid catalysts is assessed with respect to the esterification of acetic acid with butanol. The ion-exchange resins Amberlyst 15 and Smopex-101, the acid zeolites H-ZSM-5, H-MOR, H-BETA and H-USY, and the solid superacids sulphated zirconia and niobium acid are selected. Comparative esterification experiments have been carried out using the homogeneous catalysts sulphuric acid, p toluenesulphuric acid and a heteropolyacid (HPA). The weight-based activity of the heterogeneous catalysts tested is maximum for Smopex 101. The following table gives the activity of different catalysts in the esterification reaction between acetic acid and butanol at 75^(@)C . Here: k_(obs) : observed reaction rate constant ( m^(3) mol^(-1)s^(-1) ) kc catalysed reaction rate constant ( m^(3)mol^(-1) g_(cat)^(-1)s^(-1) ) Please note: k c = k obs/ amount (in g) (source: PETERS, T., BENES, N., HOLMEN, A., & KEURENTJES, J. (2006). Comparison of commercial solid acid catalysts for the esterification of acetic acid with butanol. Applied Catalysis A: General, 297(2), 182-188. doi:10.1016/j.apcata.2005.09.00) Catalysts used in oil refining industry are:

Correct the definitions of certain terms given below by changing only one word. (i) Compost: Substances converted into manure for use in industries. (ii) Landfill: Garbage buried under water in an area. (iii) Recycling: Reuse of unused material in the same or another form.