Section: Score: true if the statement is correct and write false if the statement is wrong. 1. Combustion of coal and combustion of hydrogen are examples of combination reactions. 2. Hydrogen burns in the presence of oxygen to form water in the form of steam. Upon cooling, it becomes liquid 3. Formation of sulphuric acid from Sulphur trioxide is also a combination reaction. 4. Ferrous sulphide is formed by heating fine pieces of iron with Sulphur powder. 5. The manufacture of ammonia gas from nitrogen and oxygen is also a combination reaction. 6. Sodium hydroxide combines with water to form sodium bicarbonate. 7. A combination reaction is a general category of chemical reactions. 8. Combination reactions are also known as combustion.​