Chemistry

How do you measure the rate of a reaction? - Ans .By measuring the quantity of a reactant used or the quantity of product formed over time What is the equation for calculating the mean rate of a reaction by measuring the amount of reactant used? - Ans .Mean rate of reaction = quantity of reactant used/time taken What is the equation for calculating the mean rate of a reaction by measuring the amount of product formed? - Ans .Mean rate of reaction = quantity of product formed/time take...

▪ How would you describe the pH of carbon dioxide - Ans .slightly acidic ▪ Why is it bad for plastic bags to be burned - Ans .Release toxic gases that are bad for human health and release greenhouse gases that harm the environment ▪ If talking about bromine water etc, what is the term used when the liquid has no colour - Ans .colourless (NOT CLEAR) ▪ What are the particles involved in ionic bonding - Ans .Ions ▪ What would sodium hydroxide not do in water and what is the word eq...

atom - Ans .smallest particle of an element proton - Ans .- positively charged particle - has a mass of 1 and a charge of +1 - found in the nucleus of the atom. neutron - Ans .- has no charge(neutral) and a mass of 1. - found in the nucleus of an atom electron - Ans .- a negatively charged particle - has a mass 1/2000 - found in energy levels which surround the nucleus. atomic number - Ans .the number of protons and electrons atomic mass - Ans .the total number of protons and neutron...

*Chromatography* - Ans .-Chromatography is a method used by chemists to separate out mixtures. -Chromatography works because different dyes move up the paper and different rates. -Some will stick to the paper and others will dissolve more readily in the solvent and travel more quickly. -You can com[are different chromatograms to work out what dyes are in the unknown substance. *Ionic Bonding* - Ans .-In ionic bonding, atoms lose or gain electrons to formed charged particles which are...

What is an element? - Ans .A substance that contains only one type of atom Atom - Ans .Smallest particle of an element Isotope - Ans .each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element. What substances are found in the periodic table? - Ans .Elements Where are the metals found in the pe...

What are the 3 states of matter? - Ans .Solid, liquid and gas What is the process for extracting iron form its ore? - Ans .Heat it with carbon (coke) in a blast furnace Why is carbon used for extracting iron from ore? - Ans .It is more reactive What is chromatography used to separate? - Ans .A mixture of pigments How do you calculate Rf values? - Ans .Distance pigment moved/Distance solvent moved What force holds oppositely charged ions together? - Ans .Electrostatic Which state of matte...

1. How long is Paper 1, and what does it assess? - Ans .Paper 1 of the AQA GCSE Higher Chemistry (Single Science) course lasts for 1 hour and 45 minutes, and assesses content from Atomic Structure & The Periodic Table; Bonding, Structure & The Properties of Matter; Quantitative Chemistry, Chemical Changes; and Energy Changes. 2. What is the radius of an atom? - Ans .The radius of an atom is 0.1 nanometers (1x10^-10m). 3. What are the masses and charges of the three subatomic particles th...

What are the properties of group 1 metals? - Ans .Can be cut with a knife Shiny, but tarnish quickly with air, because a layer of oxide is formed Good conductors of electricity (Like all metals) Low density Low melting point What are the properties of group 7? - Ans .• All gain an electron during their reactions • They are poisonous • 7 electrons in their outer shells • when they gain an electron they form hallide ions What is the trend in reactivity of group 1? - Ans .The react...

▪ mass - Ans .mr x moles ▪ Avogadro constant - Ans .6.02 x 10²³ ▪ conservation of mass - Ans .total mass of products = total mass of reactants ▪ volume - Ans .mol x 24dm³ ▪ concentration - Ans .mol / volume (dm³) ▪ percentage yield - Ans .yield from reaction/yield meant to be x 100 ▪ atom economy - Ans .mr of desired products/mr of all products(or reactants) x 100 ▪ endothermic - Ans .+ ▪ exothermic - Ans .- ▪ metal + acid --> - Ans .salt + hydrogen ▪ acid ...