Ex. 1 Read and translate the text Organic and Redox reactions Organic reactions occur between organic molecules (molecules which contain carbon and hydrogen). There are many organic reactions. However, functional groups determine many of the characteristics of organic molecules.
Another key concept in organic reactions is Lewis basicity. Parts of organic molecules are electrophillic or nucleophillic. Nucleophillic regions have an excess of electrons—they act as Lewis bases—whereas electrophillic areas are electron deficient and act as Lewis acids. The nucleophillic and electrophillic regions attract and react with each other.
Redox is an abbreviation of reduction/oxidation reactions. This is exactly what happens in a redox reaction, one species is reduced and another is oxidized. Reduction involves a gain of electrons and oxidation involves a loss, so a redox reaction is a reaction in which electrons are transferred between species. Reactions where something is “burnt» are the examples of redox reactions, however, oxidation reactions also occur in solution.
Redox reactions are often written as two half-reactions and show the reduction and oxidation processes separately. These half-reactions are balanced and added together to form the full equation. When magnesium is burnt in oxygen, it loses electrons (it is oxidized). Conversely, the oxygen gains electrons from the magnesium (it is reduced).
Ex. 2 Answer the questions 1. What is an organic reaction?
2. What is the key concept in organic reactions?
3. What happens when magnesium is burnt?
4. What types of organic reactions do you know?
5. How do you understand electrophillic reactions?
Ex. 3 Remake the following sentences using comparative constructions as..as and not as..as For example: Magnesium is brittle. Copper is brittle too. Magnesium is as brittle as chromium.
Magnesium is brittle but copper is not brittle. Magnesium is not as brittle as chromium.
1. Reduction process is a difficult process. Oxidation is a difficult process too.
2. Organic reactions are electron-gaining reactions. Redox reactions are not electron-gaining reactions.
3. Nucleophillic regions are electron – excessive regions. Electrophillic regions are electron – excessive too.
4. Lewis acids are hard soluble. Bronsted acids are not hard soluble.
5. Magnesium is slightly soluble. Manganese is not slightly-soluble.
6. Boric acid is a strong acid whereas hydrochloric acid is not a strong acid.
7. Sulfuric acid is a weak acid. Boric acid is a weak acid too.
