Chemistry

• What topics are covered in AQA GCC chemistry paper 1?

  Atoms, bonding, quantitative chemistry, energy changes
• What is a compound?

  A substance with two or more different atoms bonded
• What is the chemical formula for water?

  H2O
• How many hydrogen atoms are in one water molecule?

  Two hydrogen atoms
• What do we do if there's no number after a symbol in a chemical formula?

  Assume there is an invisible one
• What must be true about the number of atoms in a chemical reaction?

  They must be the same on both sides
• What is the first step in balancing a chemical equation?

  Balance atoms only in compounds first
• What is a mixture?

  A combination of elements and compounds not bonded
• What is an example of a mixture?

  Air
• How can you separate large insoluble particles from a liquid?

  Using filtration
• What is crystallization used for?

  To separate a solute from a solvent
• What is distillation?

  Heating a solution to separate liquids
• What is fractional distillation?

  Separating liquids with different boiling points
• What are the three main states of matter?

  Solid, liquid, gas
• How do particles behave in a solid?

  They vibrate around fixed positions
• What happens to particles when a substance melts?

  They gain energy and move more freely
• What do we call the process of a solid turning into a liquid?

  Melting
• What is the state symbol for a solid?


  (s)
• Who proposed the plum pudding model of the atom?

  JJ Thompson
• What did Rutherford discover about the atom?

  It has a small, dense nucleus
• What are electrons said to do around the nucleus?

  Orbit at relatively far distances
• What are protons and neutrons collectively called?

  Nucleons
• What is the charge of a neutron?

  Zero
• What does the atomic number represent?

  The number of protons in the nucleus
• What happens when an atom gains or loses electrons?

  It becomes an ion
• What is the mass number?

  The total number of protons and neutrons
• What are isotopes?

  Atoms of the same element with different neutrons
• What is relative abundance?

  The percentage of each isotope in a sample
• How is the average relative atomic mass calculated?

  By averaging the masses of isotopes
• What did Dimitri Mendeleev contribute to the periodic table?

  Grouped elements by properties, not atomic weight
• How do electrons fill the shells around the nucleus?

  From the inside out, with specific maximums
• What is the maximum number of electrons in the first shell?

  Two electrons
• What are the properties of metals?

  They donate electrons and conduct electricity
• What do nonmetals do when bonding?

  They accept electrons to fill their outer shell
• What are alkali metals known for?

  Having one electron in their outer shell
• How does reactivity change in alkali metals down the group?

  It increases as you go down
• What are halogens known for?

  Having seven electrons in their outer shell
• How does reactivity change in halogens down the group?

  It decreases as you go down
• What are noble gases known for?

  Having full outer shells and being unreactive
• What happens to metals when they lose electrons?

  They become positively charged ions