Name the four stages considered in a life cycle assessment of a product.

Making the material and the product from raw materials, using the product, transporting it, and disposing of it at the end of its life.

What is the purpose of carrying out a life cycle assessment?

To judge the total use of resources and the environmental impact of a product across its whole life.

A quarry is dug to obtain the clay for a brick. Which stage of a life cycle assessment does this belong to?

Obtaining the raw material and making the product.

A plastic bag is buried in landfill and does not break down. Which stage of a life cycle assessment does this belong to?

Disposal at the end of the product's life.

OCR GCSE Chemistry A J248

Chemical Reactions

Topic overview Writing formulae of elements and compounds Balanced equations, and deducing formulae from ions Ionic equations, and state symbols The mole and the Avogadro constant Conservation of mass, and changes of mass in open systems Stoichiometry, and calculating reacting masses Exothermic and endothermic reactions, and reaction profiles Activation energy, and bond energy calculations Oxidation and reduction, by oxygen and by electrons Acids, alkalis and neutralisation The ionic equation for neutralisation, and reactions of acids Dilute and concentrated, weak and strong The pH scale, and hydrogen ion concentration pH as a factor of ten, and measuring pH Products at the electrodes, and molten ionic compounds Electrolysis of aqueous solutions Inert and non-inert electrodes

Elements, Compounds and Mixtures

Topic overview Purity, and melting point data Relative formula mass and empirical formulae Formulations, and separating mixtures Paper and thin layer chromatography Interpreting chromatograms and Rf values Choosing a purification method Metals and non-metals in the Periodic Table Electron arrangement and position in the Periodic Table Ionic, covalent and metallic bonding compared Dot and cross diagrams, and the limits of models Reactions, electron arrangement and Mendeleev's table Carbon's four bonds, and the variety of organic compounds Diamond, graphite, fullerenes and graphene Bond strength, intermolecular forces and predicting state Bulk properties of ionic, molecular and giant structures Nanoparticles: size and surface area to volume Uses and risks of nanoparticulate materials

Global Challenges

Topic overview Extracting metals by reduction and by electrolysis Biological methods of metal extraction Rate against yield in industry, and reaction conditions The Haber process and fertiliser production Nitrogen, phosphorus and potassium in agriculture Life cycle assessment Recycling, and the decisions behind it Alloys, and the corrosion of metals Comparing glass, ceramics, polymers, composites and metals Functional groups and homologous series Predicting the products of organic reactions Addition polymerisation Condensation polymerisation, and making a polymer DNA and other natural polymers Fractional distillation of crude oil The fractions, and crude oil as a feedstock Dependence on hydrocarbons, and cracking Chemical cells and fuel cells The Earth's early atmosphere, and how oxygen developed The greenhouse effect, and evidence for climate change Effects of carbon dioxide and methane, and air pollutants Producing potable water

Monitoring and Controlling Chemical Reactions

Topic overview Concentration in mol/dm³, and titration Titration calculations, and the mass of a solute Molar gas volume and the volumes of gases Theoretical mass and percentage yield Atom economy, and choosing a reaction pathway Measuring the rate of a reaction, and rate graphs Factors affecting rate, and collision theory Surface area and rate Catalysts and how they work Reversible reactions and dynamic equilibrium Changing the conditions of an equilibrium Activation energy, and enzymes as catalysts

Particles

Topic overview The particle model and changes of state Limitations of the particle model How the atomic model changed, and the structure of the atom The size of atoms, and the subatomic particles Calculating protons, neutrons and electrons

Predicting and Identifying Reactions

Topic overview Groups 1, 7 and 0, and why they behave as they do Transition metals Predicting reactivity from the Periodic Table Reactivity of metals with water and acids Tests for oxygen, hydrogen, carbon dioxide and chlorine Tests for aqueous cations and anions Flame tests, and identifying metal ions Identifying a species from test results Instrumental methods of analysis

Global Challenges

Life cycle assessment

2 things to know
Paper 4

Overview

The four stages of a life cycle assessment, placing quarrying, product use, transport and landfill in them, what is measured at each stage, and why comparing two products fairly is difficult.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Process

Electricity is used to run a washing machine for ten years. Which stage of a life cycle assessment does this belong to?

Process

Lorries carry bottles from the factory to shops across the country. Which stage of a life cycle assessment does this belong to?

Questions from this subtopic

Each one with the model answer underneath.

1
Name the four stages considered in a life cycle assessment of a product.
Model answer
Making the material and the product from raw materials, using the product, transporting it, and disposing of it at the end of its life.
2
What is the purpose of carrying out a life cycle assessment?
Model answer
To judge the total use of resources and the environmental impact of a product across its whole life.
3
A quarry is dug to obtain the clay for a brick. Which stage of a life cycle assessment does this belong to?
Model answer
Obtaining the raw material and making the product.
4
Electricity is used to run a washing machine for ten years. Which stage of a life cycle assessment does this belong to?
Model answer
The use of the product.
5
Lorries carry bottles from the factory to shops across the country. Which stage of a life cycle assessment does this belong to?
Model answer
Transport of the product.
6
A plastic bag is buried in landfill and does not break down. Which stage of a life cycle assessment does this belong to?
Model answer
Disposal at the end of the product's life.

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Chemical Reactions

Elements, Compounds and Mixtures

Global Challenges

Monitoring and Controlling Chemical Reactions

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