Chemistry Paper 1

• 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 does it mean if there is no number after a chemical symbol?

  It indicates an invisible one atom
• What do chemical reactions involve regarding atoms?

  Atoms change their bonds and connections
• What is a word equation?

  A representation of a chemical reaction using words
• Why must chemical equations be balanced?

  Atoms are not created or destroyed in reactions
• What is the first step in balancing a chemical equation?

  Balance atoms only in compounds first
• How do you balance hydrogen atoms in a reaction?

  Put a number in front of H2O
• What is a mixture?

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

  Air
• How can you separate sand from water?

  Using filtration
• What does crystallization do?

  Leaves a solid dissolved in a liquid behind
• What is distillation used for?

  To separate 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 water is in gas form?

  Particles are far apart and move randomly
• What must be supplied to melt or evaporate a substance?

  Energy, usually in the form of heat
• What do state symbols indicate in chemical equations?

  The state of substances involved
• What does the symbol 's' represent?

  Solid
• What does the symbol 'l' represent?

  Liquid
• What does the symbol 'g' represent?

  Gas
• What does 'aq' stand for?

  Aqueous, meaning dissolved in solution
• Who discovered that atoms are made of positive and negative charges?

  JJ Thompson
• What model did JJ Thompson propose?

  The plum pudding model
• What did Rutherford discover about the nucleus?

  It is incredibly small and positive
• What did Neil's Bohr discover about electrons?

  They exist in shells or orbitals
• What are neutrons and protons?

  Neutrons are neutral; protons are positive
• What is the relative mass of protons and neutrons?

  One
• What is the charge of an electron?

  Negative one
• What does the atomic number represent?

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

  It becomes an ion
• What does the mass number indicate?

  Number of protons and neutrons in the nucleus
• How many neutrons does carbon-12 have?

  Six neutrons
• What are isotopes?

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

  Percentage of isotopes in a sample
• How is the average relative atomic mass calculated?

  Add total masses of isotopes, divide by 100
• What did Dmitri Mendeleev do with the periodic table?

  Grouped elements by properties, not just atomic weight
• What is the maximum number of electrons in the first shell?

  Two electrons