Atom economy - Study guides, Revision notes & Summaries

Chemistry AQA AS EXAM 2024 QUESTIONS WITH 100% CORRECT ANSWERS Mass number - ANSWERS Total number of protons and neutrons. Atomic number - ANSWERS Numbers of protons in the nucleus and number of electrons in shells. Negative Ions - ANSWERS More electrons than protons. Positive ions - ANSWERS More protons than electrons. Relative isotopic mass - ANSWERS mass of an atom of an isotope of an element on a scale where an atom of carbon12 is 12. Relative atomic mass - ANSWERS average mass o...

AQA CHEMISTRY A LEVEL WITH COMPLETE SOLUTIONS covalent bond - ANSWER-a shared pair of electrons between non-metal elements co-ordinate bond - ANSWER-a shared pair of electrons where both electrons are supplied by one atom repulsion in shapes of molecules - ANSWER-Lone pair-lone pair > lone pair-bonding pair > bonding pair-bonding pair electronegativity - ANSWER-the power of an atom to attract the pair of electrons in a covalent bond hess' law - ANSWER-Total enthalpy chang...

A LEVEL CHEMISTRY EXAM WITH COMPLETE SOLUTIONS   alkali - A type of base that dissolves in water forming hydroxide ions, OH- (aq) ions. alkanes - The homologous series with the general formula: CnH2n+2. alkyl group - An alkane with a hydrogen atom removed, e.g. CH3, C2H5; alkyl groups are often shown as 'R'. amount of substance - The quantity whose unit of the mole. Chemists use 'amount of substance' as a means of counting atoms. anhydrous - A substance tha...

1. Acid - Ans .A species that is a proton donor. 2. Activation energy - Ans .The minimum amount of kinetic energy that particles need to have in order to react when they collide 3. Addition polymer - Ans .A very long molecular chain formed by repeated addition reactions of many unsaturated alkene molecules (monomers). 4. Addition polymerisation - Ans .The process in which unsaturated alkene molecules (monomers) add on to a growing polymer chain one at a time to form a very long saturate...

2 OCR 2023 SECTION A You should spend a maximum of 25 minutes on this section. Write your answer to each question in the box provided. 1 Which statement explains the trend in boiling points down the halogens group? A Covalent bonds become stronger. B Induced dipole–dipole interactions (London forces) become stronger. C Ionic bonds become stronger. D Permanent dipole–dipole interactions become stronger. Your answer [1] 2 A hydrocarbon contains 85.71% carbon by mass. What is the em...

AQA CHEMISTRY A LEVEL WITH COMPLETE SOLUTIONS covalent bond - ANSWER-a shared pair of electrons between non-metal elements co-ordinate bond - ANSWER-a shared pair of electrons where both electrons are supplied by one atom repulsion in shapes of molecules - ANSWER-Lone pair-lone pair > lone pair-bonding pair > bonding pair-bonding pair electronegativity - ANSWER-the power of an atom to attract the pair of electrons in a covalent bond hess' law - ANSWER-Total enthalpy chang...

2 OCR 2023 Section A You should spend a maximum of 40 minutes on this section. Write your answer to each question in the box provided. 1 Which row is correct for the properties of substances with the bonding types shown? Bonding type Melting point Electrical conductivity Solid Molten A covalent network low poor poor B ionic high good good C metallic high poor good D simple molecular low poor poor Your answer [1] 2 Helium-4 is formed by a nuclear fusion reaction. 2 3He 4He + .....

A LEVEL CHEMISTRY EXAM WITH COMPLETE SOLUTIONS   alkali - A type of base that dissolves in water forming hydroxide ions, OH- (aq) ions. alkanes - The homologous series with the general formula: CnH2n+2. alkyl group - An alkane with a hydrogen atom removed, e.g. CH3, C2H5; alkyl groups are often shown as 'R'. amount of substance - The quantity whose unit of the mole. Chemists use 'amount of substance' as a means of counting atoms. anhydrous - A substance tha...

What is Avagadro's constant? Correct Answer 6.02 x 10^23 number of particles in a mol Define empirical formula Correct Answer The simplest whole number ratio of atoms of each element present in a compound Define molecular formula Correct Answer The number and type of atoms of each element in a molecule What is water of crystallisation? Correct Answer Water molecules that are bonded into a crystalline structure of a compound What is the ideal gas equation? What are the units of each ...

Relative atomic mass The average mass of an atom of an element, relative to 1/12th of the mass of an atom of Carbon-12 Relative molecular mass Average mass of a molecule compared to 1/12th of the mass of a carbon-12 atom The Avogradro constant the number of particles in a mole ideal gas equation pV = nRT empirical formula the simplest whole number ratio of atoms of each element in a compound percentage atom economy (Mass of desired product/total mass of reactants) x 100