Separate Chemistry II - GCSE Edexcel

These flashcards cover key concepts, definitions, and significant details from the lecture notes on the properties of matter, nanoparticles, alcohols, carboxylic acids, polymers, and methods of analysis.

What are the three categories of particles based on size?

Coarse particles, fine particles, and nanoparticles.

What is the size range for nanoparticles?

Nanoparticles are between 1 and 100 nanometres in size.

What is nanoscience?

The research into the production and application of nanoparticles.

What is a unique property of nanoparticles?

They have a very high surface area to volume ratio.

How does the surface area to volume ratio change as particles decrease in size?

As the size decreases, the surface area to volume ratio increases.

What is an example of nanoparticles made of carbon?

Fullerenes.

How do nanoparticles behave differently from bulk materials?

Nanoparticles may have different properties compared to the same materials in bulk due to their high surface area to volume ratio.

What are fullerenes used for in medicine?

They are used in drug design as they can deliver drugs to target areas more effectively.

What is the main industrial application of nanoparticles?

Catalysing reactions, due to their high surface area to volume ratios.

What property of titanium dioxide nanoparticles is utilized in sunscreens?

They block UV light but leave no white marks on the skin.

What potential risks are associated with nanoparticles?

There is a lack of understanding on how they may affect health, with potential long-term side effects.

What are the physical properties of glass?

Transparent, strong, and insulates against heat.

What is soda-lime glass made from?

A mixture of limestone, sand, and sodium carbonate heated until it melts.

What characteristic of clay ceramics makes them suitable for building?

They are hardened materials that resist compressive forces.

What is a composite material?

Made from two components: reinforcement and matrix.

Why are metals often used in electrical cabling?

Because they are good conductors of heat and electricity.

What is the primary advantage of using aluminium in construction?

It has a high strength-to-weight ratio.

What is the primary structural feature of polymers?

Large molecules made by linking together many smaller molecules called monomers.

What defines addition polymers?

Formed by the joining of monomers that contain C=C bonds.

What type of linkage is formed in condensation polymers?

An ester linkage, with the removal of a small molecule, usually water.

What are the first four alcohols commonly used as fuels?

Methanol, ethanol, propanol, and butanol.

How is ethanoic acid produced from ethanol?

By oxidation when treated with oxidising agents.

What is the general formula for carboxylic acids?

alkan + oic acid.

What happens during fermentation of sugars?

Yeast turns sugars into ethanol and carbon dioxide in the absence of oxygen.

What is the boiling point of ethanol, making it easier to separate from water?

78 ºC.

What can be used to identify ions in a substance?

Chemical tests like flame tests and precipitation reactions.

How are metal cations identified in solution?

By the color of the precipitate formed when sodium hydroxide is added.

What happens to litmus paper when exposed to ammonia gas?

It turns damp red litmus paper blue.

What indicates the presence of carbonate ions in a test?

Effervescence with dilute acid and the production of CO2.

How do precipitation reactions help detect sulfate ions?

By forming a white precipitate of barium sulfate when barium chloride is added.

What does the flame test identify?

Metal ions based on the color of the flame produced.

What role does DNA serve in living organisms?

It contains genetic information necessary for organism development and function.

What do naturally occurring polymers include?

Proteins and carbohydrates such as starch.

What is the importance of proteins in biological systems?

They perform specific functions like oxygen transport (hemoglobin) and biocatalysis (enzymes).

How can polymers be recycled, and why is it challenging?

Recycling requires sorting different types of polymers, which can be tedious and expensive.

What are the advantages of instrumental methods of analysis in chemistry?

They are more accurate and faster than traditional methods.

How does flame emission spectroscopy work?

By measuring the intensity and wavelength of light emitted from heated metal ions.

What is a specific example of an addition polymer?

Poly(ethene), commonly called polythene.

What type of reaction do condensation polymers undergo?

Two different monomers react to form a polymer while releasing a small molecule, usually water.

What factors affect the properties of a composite material?

The types of reinforcement and matrix used.

What occurs during the combustion of alcohols?

They release heat energy, producing carbon dioxide and water.

What determines the distinct colors formed by metal ions in a flame test?

Different metal ions emit different wavelengths of light.

How are homologous series characterized?

Similar features and chemical properties due to the same functional group.

What happens to potassium dichromate during the oxidation of ethanol?

It changes color from orange to green.

What is the significance of the high surface area to volume ratio in nanoparticles?

It allows more surface area for reactions, making them better catalysts.

What should be avoided to prevent contamination during the flame test?

Avoid using a wire loop that is too hot to glow red.

What are the negative environmental impacts of polymer disposal?

They are non-biodegradable, leading to waste accumulation in landfills.

What does a white smoke indicate when testing for ammonia with HCl?

The formation of ammonium chloride.

What is the general formula for carbohydrates?

C(H2O)n.

What is the common relationship between monomers in a homologous series?

They differ by a constant unit, often CH2.

How is the calorimetry equation defined?

Q = m x c x ΔT.

What is the relationship between the length of an alcohol chain and its combustion energy?

Longer alcohols generally release more energy per gram.

How do enzymes function as biological catalysts?

By lowering the activation energy needed for reactions.

What is the role of nucleotides in DNA?

They are the monomers that form the genetic code.

What does incineration of polymers potentially produce?

Toxic gases such as hydrogen chloride and carbon monoxide.

How do ammonia and ammonium ions differ?

Ammonia is a gas (NH3), while ammonium is a positive ion (NH4+).

Why is purity important in synthesis and testing in chemistry?

Impurities can affect reaction outcomes and test results.

What additional information can help predict the products of organic reactions?

Knowledge of the functional groups of reactants.

What are the two main categories of natural polymers?

Proteins and polysaccharides.

How does the structure of starch allow it to function?

It serves as an energy storage molecule in plants.

What happens to the enzyme activity at extreme temperatures?

Enzymes may denature and lose functionality.

What reaction type do alcohols undergo to form carboxylic acids?

Oxidation.

What are the benefits of using renewable sources for materials?

They reduce waste and minimize environmental impact.

What is the main feature separating hydration from dehydration reactions?

Hydration involves adding water, whereas dehydration involves removing water.

What is an example of a condensation reaction?

Formation of esters from alcohols and acids.

What do the colors of precipitates indicate during tests for anions?

They identify the specific anion present in the solution.

What did the change in color of potassium dichromate signify during ethanol oxidation?

It indicates the conversion of ethanol to ethanoic acid.

What is the structural formula of ethanol?

C2H5OH.

How is fractional distillation utilized in the purification of ethanol?

By heating to separate ethanol from water based on boiling points.