AQA GCSE chemistry C1 Verified Solutions

AQA GCSE chemistry C1 Verified Solutions 1. What is the central part of an atom called? Answer: The nucleus 2. What are the charges and relative masses of protons, electrons, and neutrons? Answer: Protons: +1, 1; Electrons: -1, 0.0005; Neutrons: 0, 1 3. Why are atoms neutral? Answer: Because the positive charge of protons and zero charge of neutrons are balanced by the negative charge of electrons 4. What is the difference between an element and a compound? Answer: An element is a substance composed of only one type of atom, while a compound is a substance formed by combining two or more elements chemically 5. What do elements in the same group have in common? Answer: Elements in the same group share similar chemical properties due to having similar electron configurations 6. What is unique to each element in terms of its atomic structure? Answer: The number of protons, electrons, or neutrons can vary between elements 7. Where are metals typically found on the periodic table? Answer: Metals are found in the large block between groups 2-3 8. Why are noble gases unreactive? Answer: Noble gases have a full outer shell of electrons, making them resistant to gaining or sharing electrons 9. How do we determine the number of protons and electrons in an element? Answer: The atomic number gives us the number of protons and electrons, as they are equal for a neutral element 10. How do we determine the number of neutrons in an element? Answer: By subtracting the atomic number from the mass number 11. What are the rules for filling electron shells? Answer: The first shell can hold up to 2 electrons, the second shell up to 8 electrons, and the third shell up to 8 electrons 12. Why do elements react with each other? Answer: Elements react to gain or share electrons to fill their outer shells 13. What does the group number of an element reveal about its electron arrangement? Answer: The group number indicates the number of electrons in the outermost sh