What are some examples of reactions with high atom economy?

Examples of reactions with high atom economy include the Haber process, the Ostwald process, and the Contact process.

The Haber process is a method used to manufacture ammonia from nitrogen and hydrogen. This reaction has a high atom economy because all the atoms in the reactants are used to make the product. The equation for the Haber process is N2(g) + 3H2(g) → 2NH3(g). As you can see, all the atoms in the reactants are used to make ammonia, so there are no waste products.

The Ostwald process is another example of a reaction with high atom economy. It is used to produce nitric acid from ammonia. The overall equation for the Ostwald process is 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g), followed by 2NO(g) + O2(g) → 2NO2(g), and finally 3NO2(g) + H2O(l) → 2HNO3(aq) + NO(g). Again, all the atoms in the reactants are used to make the products, so there are no waste products.

The Contact process is used to manufacture sulphuric acid from sulphur dioxide. The overall equation for the Contact process is 2SO2(g) + O2(g) → 2SO3(g), followed by SO3(g) + H2O(l) → H2SO4(aq). This reaction also has a high atom economy because all the atoms in the reactants are used to make the product.

In all these processes, the high atom economy is beneficial because it means that resources are used efficiently, and the amount of waste is minimised. This is not only cost-effective but also better for the environment.