Question

Describe how you personally experience acid/base chemistry in your own daily life. The context could be nutritional, medicinal, agricultural, industrial, commercial, or any other relevant application of your choice. Are neutralization reactions reversible? Explain. How do industrial and vehicular emissions contribute to the ongoing problem of acid rain? Describe how acidification of water may be damaging to buildings, forests, or human health. Research and briefly describe a real-life application of chemical equilibrium. How do we as a society benefit from equilibrium-driven processes? Sample contexts may include nutritional, medicinal, agricultural, industrial, commercial, or any other relevant application of your choice.

Answer 1

1. Acid/base chemistry in daily life: acid-base reaction or neutralisation reaction are pretty common in daily life. we are using this chemistry every day, in every field like agricultural, medicinal, industrial etc, without paying much attention to it.

Here are some examples :

i. Bee stings: the liquid of Bee is acidic in nature. The usual home remedy is to apply lime(basic) on the place where the Bee stung. Sometimes we apply acidic things like lemon in case of wasp or other insects since their liquid is more of basic in nature.

ii. People in India like to have 'Paan' (beetle leaf)  after lunch or dinner. There is a scientific reason behind it. The lime inside the paan, which is basic in nature neutralises the excess acid generated inside the stomach.

iii. the purpose of using sodium bicarbonate in the bakery is to produce lots of carbon di oxide gas , when mixed with acidic products, or acid generated from yeast. This makes bakery products more fluppy.

iv.In the agricultural field, farmers use "khaad", which are nothing but mixtures of brunt woods, rotten leaves, ashes, stored cow stung etc, actually basic in nature, and are used to neutralise the acidic soil.

v. medicines used for acidic stomach upset are actually made up of bases like magnesium or aluminium hydroxides.

There are many more examples like this.

2. Yes, neutralisation reaction is reversible. In principle, all the reactions are reversible, but it depends on conditions and time. Although we don't see it happening the reverse way, like in the above-mentioned examples, Theoretically it is feasible and practically it is possible provided the right reaction condition. Opposite of neutralisation is hydrolysis. this is also a common reaction.

3. Industries like power plants and vehicles release gases like dihydrogen sulfide(H2S), Nitrogen oxides in the air,  which with air vapour and during lightening, it makes hard acids like sulphuric acid, nitric acid etc. this acid comes with rainwater, and called acid rain. this not only damages old monuments or new buildings, but it also causes several damages to corp and forest and public health.

4. When two or more reactants come close to each other, and the proper condition is applied (say A and B), reaction forward towards the product , and products are formed (say C and D). the same time a backword reaction also starts, from product to the initial reactant.

If the two reactions take place at the same rate, a condition of chemical equilibrium is achieved. Now, if this condition is achieved, reactions will not be completed in any direction. That means, there will always some reactant and products together. To move this equilibrium in favour of any particular direction, reaction conditions have to be optimized.

Here comes the Le Chatelier Principle, to predict the effect of change in condition on chemical equilibrium. It states that, whenever we impose a change in the condition of the reaction ( like concentration, temperature, volume etc), the system will shift the equilibrium to adjust the change, and adjust the amount of substances(reactants and products).

Here are some examples:

i. in the industrial production of lime from limestone, (decomposition of calcium carbonate into calcium oxide and carbon dioxide), the forward reaction is endothermic, so, increase in temperature move the reaction equilibria towards the lime.

Increase in pressure will favour the backword reaction, so the reaction is carried out in atmospheric pressure and open system, so that carbon dioxide can be removed from the reaction system easily, (concentration of CO2 reduced) and backword reaction can be prohibited.

ii. in the Haber process of ammonia sysnthesis( N2 + H2 <=> NH3), the backword reaction is endothermic, so increase in temperature will shift the equilibria away from the product. So it is carried out in low temperature.

but the increase in pressure will favour the equilibrium towards the product, and thus carried out high pressure.

iii. haemoglobin reacts with oxygen and make a red complex, this is how oxygen is carried out in human body. In high altitude , where oxygen pressure is less, the reaction equilibraia shifts away from this complex, and body fainted(light colored).