Question

The catalyst used in the hydrogenation of oils is: (a) \(\mathrm{Fe}\) (b) Ni (c) \(\mathrm{Pt}\) (d) \(\mathrm{V}_{2} \mathrm{O}_{5}\)

Short answer

The catalyst used in the hydrogenation of oils is (b) Ni.

Step-by-step solution

Identify the Purpose of the Catalyst

The purpose of the catalyst in the hydrogenation of oils is to speed up the reaction by providing an alternative pathway for the reaction with a lower activation energy. The catalyst is not consumed in the reaction.

Recall Common Catalysts

Recall from chemistry knowledge that certain metals are known to act as catalysts for hydrogenation reactions. These include Nickel (Ni), Palladium (Pd), Platinum (Pt), and sometimes Raney Nickel, which is a finely divided form of Nickel.

Choose the Correct Option

Considering the common catalysts used in hydrogenation, we can identify that Nickel (Ni) is the most widely used catalyst for hydrogenation of oils.

Key concepts

Catalysis in Chemistry

In chemistry, catalysts are remarkable substances that can speed up the rate of chemical reactions without undergoing permanent chemical changes themselves. They achieve this by providing an alternative pathway for the reaction to occur, which requires less energy. For instance, in the hydrogenation of oils, a catalyst is essential for converting unsaturated fats to saturated fats by adding hydrogen to the oil molecules in a more efficient manner.

Catalysts work by lowering the activation energy needed for a reaction, which allows the reaction to proceed at a faster rate even at lower temperatures. This is particularly important in industrial processes, where time and energy efficiency are key considerations. In the step-by-step solution provided, Nickel (Ni) is identified as the widely used catalyst in the hydrogenation of oils. This is due to its effectiveness in bonding with hydrogen and oil molecules, thus lowering the energy barrier for the reaction and increasing the rate at which hydrogen atoms are added to the oil, transforming it into a solid form at room temperature.

Chemical Reactions in Physical Chemistry

Physical chemistry is the branch that deals with how matter behaves on a molecular and atomic level and how chemical reactions occur. Understanding the details of the chemical reactions is crucial for controlling and optimizing these processes. The hydrogenation of oils is a chemical reaction where unsaturated fat molecules (which contain double bonds) are converted into saturated fat molecules (without double bonds) by the addition of hydrogen atoms.

Reactants like oils and hydrogen typically require specific conditions to react at a noticeable rate. Factors including temperature, pressure, and the presence of a catalyst can greatly influence the rate of the reaction. In the context of hydrogenation, the role of a catalyst such as Nickel (Ni) is to create a favorable environment on its surface where the reactants can come together more readily, thereby enhancing the reaction rate without the need for extreme conditions.

Activation Energy in Reactions

Activation energy is the minimum energy that must be available to a chemical system with potential reactants to result in a chemical reaction. Essentially, it's the 'energy barrier' that needs to be overcome for reactants to be transformed into products. In every chemical reaction, molecules must collide with sufficient energy for the reaction to occur.

In the example of oil hydrogenation, the activation energy is the threshold that hydrogen and oil molecules must surpass to react and form saturated fats. Catalysts like Nickel (Ni) play a pivotal role by lowering this activation energy, thereby enabling the reaction to take place more readily. They act by stabilizing the transition state, reducing the amount of energy that the molecules must have for the reaction to proceed. As such, even at room temperature, where kinetic energy of the molecules is comparatively lower, the presence of a catalyst can make it feasible for the hydrogenation reaction to take place efficiently.