How fast reactants change into products. 

What is the slowest rate of reaction example?

What is a moderate rate of reaction example?

°Collision frequency. °Energy transferred.   °Temperature.   °Increasing concentration   °Increasing pressure.   °Increasing Surface area. °Catalyst

What 7 things does the rate of reaction depend on?

Particles have to collide with enough energy to be successful. 

Temperature increases kinetic energy in the particles, making them collide more frequently. 

More particles collide in the same volume of water- Frequent collisions. 

Depends on Increasing concentration- How?

Same number of particles occupy a smaller space, leading to more frequent collisions. 

Increased surface area : volume ratio means that particles will have more area to work on, leading to more frequent collisions. 

Decreases activation energy by making an alternative reaction pathway with lower activation energy. 

Substance that speeds up a reaction without being used up. 

Minimum amount of energy needed for particles to react by breaking bonds of reactants. 

Amount of reactant used or formed % time. 

When a forward reaction goes at the same rate as a backward reaction——-> Both reactions are happening but there is no effect as concentrations reached a balance so won’t change. 

Where is the only place equilibrium can be reached?

What 3 things does equilibrium depend on?

Endothermic on other.   ——>    Both energy transferred is equal. 

Water + Anhydrous copper sulfate (white) =

1)Add SODIUM THIOSULFATE in conical flask.   2)Place flask on paper with black cross.   3)Add HCL to flask & start stopwatch.   4)When cross disappears, note down the time.   5)Repeat with different concentrations of Sodium thiosulfate and HCL.    

Measuring rates of reaction PRACTICAL : Precipitation or colour change. 

-Cannot be applied on graphs as visual change may be bias. 

What is a disadvantage of Precipitation or colour change?

1)Add HCL to conical flask & place on mass balance. 2)Add magnesium ribbon & plug with cotton wool.   3)Start stopwatch & record mass at regular intervals. 4)Plot results in a table, Work out mass lost by taking away mass change from initial mass & plot in graph. 5)Repeat with different concentrations. 

Measuring rates of reaction: Change in mass——-> Magnesium + HCL = Hydrogen gas. 

The volume of gas is collected in a gas syringe in cm3. Take measurements in regular intervals & plot a graph.                         The more gas, the faster the reaction. 

Measuring rates of reaction: Volume of gas given off= Describe the process. 

Idea that if you change the conditions of reversible reactions at equilibrium, the system will try to counteract the change. 

 Equilibrium moves to EXOTHERMIC DIRECTION to produce more HEAT. = More product formed from exothermic direction than endothermic direction. 

Le Chateliers Principle: What happens if you Decrease temperature at equilibrium?

Equilibrium moves to the ENDOTHERMIC DIRECTION to decrease temperature. = More products from endothermic than the exothermic direction. 

Le Chateliers Principle: What happens if you Increase the temperature at equilibrium?

Equilibrium moves to direction where there is fewer molecules of gas. 

Le Chateliers Principle: What happens if you increase the pressure at equilibrium?

Equilibrium moves in direction where there’s more molecules of gas. 

Le Chateliers Principle: What happens if you decrease pressure?

System decreases by making more products. 

Le Chateliers Principle: What happens if you increase reactants?

Le Chateliers Principle: What happens if you Decrease products?

System will no longer be in equilibrium. 

When concentration is changed, what happens?

Compound made from only hydrogen & carbon. 

°More Runny.       °More volatile.       °More flammable. 

The shorter the chain of hydrocarbon, the more:

Group of organic compounds that react in a similiar way. 

Alkanes are a part of the homologous series, what is that?

Alkanes are SATURATED COMPOUNDS, What is that?

°Methane=1.   °Ethane=2.    °Propane=3.   °Butane=4. 

Name the 4 types of Alkanes and how many carbons they have. 

Carbon & Hydrogen in hydrocarbon become oxidised. 

Because they release a large amount of energy when combusted. 

Fossil fuel that is formed from remains if dead plants and animals that died millions of years ago & were compressed with high underground temperatures. 

Seperated different compounds in crude oil. 

1)Heated until becomes gas, gas enters fractionating column.   2)In column, there’s a temperature gradient= hot in bottom & cool on top. Longer hydrocarbons with high BPs condenseinto liquid & drain out of column early on. Shorter hydrocarbons with lower BPs condense & drain out later on near the top where it is cooler. 3)Crude oil becomes Seperated in different fractions. Each fraction has hydrocarbons with similiar BPs & carbon atoms. 

Name the 3 steps of fractional distillation. 

polymers, solvents, lubricants, detergent. 

Orange bromine water added to alkanes turns into a colourless compound. 

Splitting long chain hydrocarbons into more useful shorter chain hydrocarbons called ALKENES. 

Because short chain hydrocarbons are more flammable. 

Why are short chain hydrocarbons (ALKENES) more useful?

Used as a starting material when making compounds for polymers. 

1)Heat long chain hydrocarbons to vapourise. 2) a pour passes through a hot aluminium oxide catalyst 3)Long chain molecules split apart on surface of catalyst. 

Vapourise hydrocarbons by heating, mix them with steam & heat to high temperature. 

Pure substances will melt/boil at a specific temperature. The closer the melting point of a substance to the value of a pure substance, the purer the sample. 

What is a typical trait of pure substances?

°Lower melting point.   °Increased melting range.   °Increased boiling point. 

Useful mixtures designed to have a specific purpose made by following a formula. 

Method to Seperated soluble substances In mixtures. 

Chemicals that stay in equilibrium with the mobile phase…..

°How soluble it is in the solvent.   °How attracted they are to the chromatography paper. 

The amount of time spent on each phase depends on….

Distance travelled by substance % distance travelled by solvent. 

Bubbling co2 in Limewater turns limewater CLOUDY. 

LIT SPLINT will create a SQUEAKY POP sound. 

1)Volcanoes erupted & released co2, ammonia, nitrogen, methane, & water vapour. 2)When water vapour condensed, it turned into oceans. 3)CO2 was absorbed by oceans to create carbonate precipitates that formed limestone & shells. 4)Algae evolved due to water & absorbed co2 by photosynthesis to release oxygen. 5)Wildlife evolved due to an increase of oxygen. 6)Organisms died & became compressed in sediments, trapping co2 underground which reduced the atmospheres co2 levels. 

Describe the 6 step evolution of the atmosphere. 

80% Nitrogen.    20% oxygen.       Many other small proportions of ammonia, methane, co2, & water vapour. 

What are the percentages of gases in the modern atmosphere?

Greenhouse gases absorb long wavelength radiation of the sun which warms the Earth. 

Deforestation, livestock, burning fossil fuels, landfill sites. 

Name 4 things that increase the greenhouse effect. 

Why is evidence for climate change reliable?

-Ice caps melt= rising sea levels= flooding= coastal erosion & damaged habitats.       -Changes rainfall patterns= affects farming.      -Sulfur dioxide causes acid rain= damages properties.    -Frequencies & severities of natural hazards increase. 

Measure of the amount of co2 an object releases throughout its lifecycle. 

°Renewable energy resources.        °Taxes placed on companies that emit greenhouse gases.           °Carbon capture.        °Governments can put on a cap on emissions of all greenhouse gases made. 

Give 4 methods of reducing carbon footprint. 

°Expensive & time consuming to research efficient alternate sources of energy.          °Impacts economic growth.           °Hard to make international agreements as countries don’t want to sacrifice their economic development.           °Individuals don’t want to make changes to lifestyle= expensive or uneducated if impacts of co2. 

Give 4 reasons why it is hard to reduce carbon footprint. 

-Releases greenhouse gases.   -Damaged landscape & habitats.  -Produces waste= increased landfill. 

Give 3 risks of extracting non renewable resources. 

Development approach that takes account the present day needs of society without damaging lives of future generations. 

How can copper be adapted for sustainability?

°BIOLEACHING= Bacteria turns copper in ore into soluble copper compounds that Seperates ore without need of combustion.   °PHYTOMINING=Growing plants in soil that has copper. 

Which processes are used to extract copper from low grade ores?

°Recycling materials= Melting & casting already extracted metals= uses less energy than extracting new metals.                °Glass Recycling= Reduces energy needed to make new glass. 

When fossil fuels/hydrocarbons become oxidised during combustion, what is released?

Plenty of oxygen is used to burn ALL fuel. 

Not enough oxygen is present & some fuel doesn’t burn= this creates PARTICULATES. 

°Respiratory problems by damage to the lungs when inhaled.              °Reflect sunlight back to space= less light reaches Earth=Global dimming. 

°Binds to haemoglobin=less co2 transported around body=Fainting, comas, passing.           

A process where every stage of a products life is assessed to find out the impacts it has on the environment. 

-Damages environment by deforestation.      -Pollution due to energy used to process & extract materials. 

Give 2 damages of getting raw materials. 

-Uses lots of energy resources=pollution due to fumes.   +Waste products can be turned into useful chemicals= reduces pollution. 

Give one damage & one advantage of Manufacturing & packaging 

-Fertilisers leach into water supplies & damage rivers & ecosystems. 

-Landfill=Pollutes land & water.      -Energy used to transport waste to landfill=pollutants.   -Burnt waste causes air pollution. 

Give 3 disadvantages of Product disposal. 

-Effect of some pollutants I’d hard to give a numerical value.    -Person carrying out assessment may be biased=unfair assessment.        -LCA can be written deliberately to support claims of companies to give them positive advertising.   

Give 3 problems with life cycle assessments. 

English (UK)

Flashcard

Diana Williamson

United Kingdom

DEFAULT (England)

Chemistry

GCSE AQA Chemistry paper 2 

Hey! Here are your GCSE AQA Chemistry Paper 2 condensed notes and revision guide in PDF. Find revision notes for Paper 1 too, topics for Chemistry Paper 2 AQA Combined, past papers, mark schemes, and more. Perfect for GCSE Chemistry exam prep.

Gcse AQA Chemistry Paper 2 Condensed Notes PDF with Revision Guide

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year 9 chemistry

year 8 chem flashcards /questions

Gcse AQA Chemistry Paper 2 Condensed Notes PDF with Revision Guide

Flashcards

year 9 chemistry

year 8 chem flashcards /questions