GCSE Chemistry OCR B J258

C6.4: How are chemicals made on an industrial scale?

#C6.4.1

recall the importance of nitrogen, phosphorus and potassium compounds in agricultural production

#C6.4.2

explain the importance of the Haber process in agricultural production and the benefits and costs of making and using fertilisers, including:

a) the balance between demand and supply of food worldwide b) the sustainability and practical issues of producing and using synthetic and natural fertilisers on a large scale c) the environmental impact of over-use of synthetic fertilisers (eutrophication)

#C6.4.3

**explain how the commercially used conditions for the Haber process are related to the availability and cost of raw materials and energy supplies, control of equilibrium position and rate including:

a) the sourcing of raw materials and production of the feedstocks; nitrogen (from air), and hydrogen (from natural gas and steam) b) the effect of a catalyst, temperature and pressure on the yield and rate of reaction c) the separation of the ammonia and recycling of unreacted nitrogen and hydrogen**

#C6.4.4

**explain the trade-off between rate of production of a desired product and position of equilibrium in some industrially important processes **

#C6.4.5

define the atom economy of a reaction

#C6.4.6

calculate the atom economy of a reaction to form a desired product from the balanced equation using the formula:

atom economy=mass of atoms in desired productmass of atoms in reactants×100\text{atom economy} = \dfrac{\text{mass of atoms in desired product}}{\text{mass of atoms in reactants}} × 100

#C6.4.7

use arithmetic computation when calculating atom economy

#C6.4.8

explain why a particular reaction pathway is chosen to produce a specified product given appropriate data such as atom economy (if not calculated), yield, rate, equilibrium position, usefulness of by-products and evaluate the sustainability of the process

#C6.4.9

describe the industrial production of fertilisers as several integrated processes using a variety of raw materials and compare with laboratory syntheses. including:

a) demand for fertilisers (including ammonium sulfate) is often met from more than one process b) some fertilisers are made as a bi-product or waste product of another process c) process flow charts are used to summarise industrial processes and give information about raw materials, stages in the process, products, by-products and waste d) lab processes prepare chemicals in batches, industrial processes are usually continuous

#C6.4.10

compare the industrial production of fertilisers with laboratory syntheses of the same products

C6.3
What factors affect the yield of chemical reactions?
C7.IaS1
What needs to be considered when investigating a phenomenon scientifically?