Q1. Anhydrous Cobalt Chloride Reaction
The word equation shows the reaction between anhydrous cobalt chloride and water.
(a) Type of Reaction
Anhydrous cobalt chloride and water undergo a chemical reaction.
(b) What Happened
When the student added water to anhydrous cobalt chloride, an exothermic reaction took place.
(c) Temperature Rise
A student measured the temperature rise when anhydrous cobalt chloride was added to water. The student's results are shown in the table below:
Trial 1: 8.5
Trial 2: 8.2
Trial 3: 8.2
The mean temperature rise is calculated as 8.3.
(d) Type of Reaction
When hydrated cobalt chloride reacts to form anhydrous cobalt chloride and water, it is a reversible reaction.
Q1. In industry, ethanol is produced by the reaction of ethene and steam at 300°C and 60 atmospheres pressure using a catalyst. The forward reaction is exothermic.
(a) Mixture from Separator
The mixture from the separator contains ethanol and water due to the reaction between ethene and steam.
(b) Effect of Increasing Temperature
According to Le Chatelier's Principle, increasing the temperature will decrease the amount of ethanol produced at equilibrium since the forward reaction is exothermic.
Ammonium nitrate is manufactured using the reaction of nitrogen and hydrogen gas.
(a) Purpose of Iron in Reactor 1
The iron in reactor 1 serves as a catalyst to increase the rate of the forward reaction.
(b) Best Yield of Ammonia at Equilibrium
(i) The best yield of ammonia is obtained at low temperature and (ii) at high pressure to favor the exothermic forward reaction.
(c) Temperature in Reactor 1
A much lower temperature is not used in reactor 1 to ensure a faster reaction rate and higher ammonia yield.
(d) Separation of Ammonia
In the separator, the mixture is cooled and compressed to separate the ammonia from the other gases.
Q2. The Haber process produces ammonia from nitrogen and hydrogen.
(a) The hydrogen is obtained from natural gas in the reactor.
(b) The reactor contains nitrogen and hydrogen at high pressure, heated and passed over a catalyst. The temperature in the reactor is 450°C.
Q2.
(i) In the chemical equation, the symbol "→" indicates the direction of the reaction.
(ii) Increasing the pressure would favor the formation of ammonia.
(iii) The electron arrangement in a molecule of ammonia is shown diagrammatically, with the nitrogen and hydrogen atoms' electron arrangements depicted.
Q2.
(i) The raw materials for ammonia production are nitrogen and hydrogen.
(ii) A temperature of 450°C is used in the Haber process to maintain an optimum balance between reaction rate and energy efficiency.
(iii) Ammonium nitrate can be produced by adding nitric acid to ammonia.
Q2.
(b) The invention of the Haber process caused the closure of the Humberstone mines in Chile due to the mass production of ammonia, which replaced the need for sodium nitrate.
Q3.
The flow chart below shows the main stages in the production of ammonium nitrate.
(i) The two raw materials shown are nitrogen and acid D.
By using reversible reactions, industry can efficiently produce important chemicals such as ethanol, ammonia, and ammonium nitrate, providing essential products for various applications. These reactions and processes play a crucial role in the chemical industry, serving as the foundation of numerous products and technologies.
