GCSE EDEXCEL TRIPLE SCIENCE CHEMISTRY

GCSE EDEXCEL TRIPLE SCIENCE CHEMISTRY PAPER 2 2024 QUESTION PAPER WITH QUESTIONS AND CORRCT ANSWERS GRADED A+ What is in the nucleus? - CORRECT ANSWER-Protons and neutrons What is relative atomic mass? - CORRECT ANSWER-Relative atomic mass is an average mass taking into account the different masses and abundances of all the isotopes that make up the element How do you calculate the relative atomic mass? - CORRECT ANSWER-Sum of (isotope abundance x isotope mass number) / sum of abundances of all the isotopes What are compounds? - CORRECT ANSWER-Substances formed from two or more elements, the atoms of each are in fixed proportions throughout the compound, and they're held together by chemical bonds What is ionic bonding? - CORRECT ANSWER-A compound formed through bonding between a metal and non-metal (consists of ions). The metals become positive as they lose electrons, and the nonmetals become negative as they lose electrons. E.g. the metal gives an electron to a chlorine atom. The oppositely charged ions are attracted to each other by electrostatic forces What are five properties of ionic compounds? - CORRECT ANSWERHigh melting points High boiling points (due to the strong bonds between the ions) Cannot conduct electricity in solid form Conduct electricity in molten form as the ions are free to move Dissolve easily in water What is covalent bonding? - CORRECT ANSWER-A compound formed from non-metals consists of molecules. Each atom shares an electron with another atom. Give an example of an ionic compound - CORRECT ANSWER-NaCl (Sodium chloride) Give an example of a compound that is covalently bonded - CORRECT ANSWER-HCl (Hydrogen chloride) What are 5 features of simple molecular structures? - CORRECT ANSWER-Weak intermolecular forces Low melting points Low boiling points Melting and boiling points increase as the molecules get bigger Don't conduct electricity What is the formula for carbon dioxide? - CORRECT ANSWER-CO2 What is the formula for ammonia? - CORRECT ANSWER-NH3