AQA GCSE Chemistry Paper 1 (Triple)

AQA GCSE Chemistry Paper 1 (Triple) 1. What is the size of an atom's nucleus? Answer: Approximately 0.1 nanometers in diameter 2. Where is the nucleus located within an atom? Answer: At the center of the atom 3. What does the nucleus consist of? Answer: Protons and neutrons 4. What is the charge of a proton? Answer: Positive 5. What is the charge of an electron? Answer: Negative 6. What is the mass of an electron? Answer: Essentially zero 7. What is the charge of a neutral atom? Answer: Zero 8. What does the atomic number reveal? Answer: The number of protons present in an atom 9. What does the mass number indicate? Answer: The total number of protons and neutrons in an atom 10. Define an element: Answer: A substance composed of only one type of atom 11. What are isotopes? Answer: Atoms with the same number of protons but different numbers of neutrons 12. How do compounds form? Answer: When two or more elements combine chemically 13. What is the composition of compounds formed between metals and non-metals? Answer: Ions (metal ions and non-metal ions) 14. How do metal atoms behave to form positive ions? Answer: They lose electrons 15. How do non-metals behave to form negative ions? Answer: They gain electrons 16. What is the composition of compounds formed between non-metals? Answer: Molecules (formed by sharing electrons) 17. Relative charges: * Proton: +1 * Neutron: 0 * Electron: -1 what is the nucleus surrounded by? ️electrons what is a balanced equation? ️an equation in which each side of the equation has the same number of atoms of each element and mass is conserved what are never created or destroyed during a chemical reaction? ️atoms the total mass of reactants = ️total mass of products how can mixtures be separated? ️by physical means, such as filtration, crystallization and simple distillation who created the key ideas successively about atoms? ️dalton thomson, rutherford and bohr what experiment did Rutherford do? ️gold foil what is the gold foil experiment? ️directed narrow beam of alpha particles at a thin sheet of gold foil what did Neils Bohr discover? ️electrons can reside only on energy levels called orbitals or shells what did dalton do? ️created the atomic theory what is the relative mass of a proton and neutron? ️1 how are the electrons in atoms arranged? ️energy levels or shells how many electrons can the first shell hold? ️2 electrons how many electrons can the second shell hold? ️8 electrons what does the number of electrons in the outermost shell determine? ️the way in which that element reacts what does the group number tell you? ️how many electrons are in the outer shell what do the atoms of metals tend to lose ️electrons what do atoms of non-metals tend to gain ️electrons why are the nobel gases in group 0 unreactive? ️because they have a very stable electron arrangement what is the pattern in group 1's melting and boiling point? ️they decrease going down the group what is the pattern in group 1's reactivity? ️it increases going down the gr