PAPER 1 REVISION

• What is the plum pudding model of the atom?

  A positive charge with electrons scattered
• Who discovered the nucleus of the atom?

  Ernest Rutherford
• What did Niels Bohr discover about electrons?

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

  Protons are positive, neutrons are neutral
• What does the atomic number represent?

  Number of protons in the nucleus
• What does the mass number indicate?

  Sum of protons and neutrons in the nucleus
• How many neutrons does a carbon atom with mass number 12 have?

  6 neutrons
• What are isotopes?

  Atoms of the same element with different neutrons
• How is density defined?

  Mass per unit volume of a material
• What is the formula for density?

  Density = mass / volume
• What is the symbol for density?

  The Greek letter row (ρ)
• Why is water vapor less dense than liquid water?

  Water vapor molecules are more spread out
• How do you find the density of a regular object?

  Calculate volume and measure mass
• What is the volume of a cuboid calculated by?

  Length × Width × Height
• What tool can be used for measuring small dimensions accurately?

  Vernier calipers
• What is the resolution of vernier calipers?

  0.1 mm
• What is the resolution of a micrometer?

  0.01 mm
• How do you find the volume of an irregular object?

  Use water displacement method
• What are the three main states of matter?

  Solid, liquid, and gas
• What happens to particles in a solid?

  They vibrate around fixed positions
• What is required to melt a solid or evaporate a liquid?

  Supply energy, usually as heat
• What is specific heat capacity?

  Energy needed to raise temperature of 1 kg
• How do you measure specific heat capacity experimentally?

  Heat a block and measure temperature change
• What happens to temperature during a change of state?

  Temperature remains constant during the change
• What is internal energy?

  Sum of kinetic and potential energy of particles
• What does an increase in temperature indicate?

  Increase in kinetic energy of particles
• What is the equation for thermal energy change?

  ΔE = mcΔT
• What does specific latent heat (SLH) measure?

  Energy needed to change state of 1 kg
• What is the SLH of fusion for water?

  334,000 J/kg
• What happens to gas particles when heated?

  They gain kinetic energy and move faster
• How does pressure increase in a gas?

  Particles collide with container walls more forcefully
• What is the relationship between pressure and volume at constant temperature?

  Pressure × Volume = constant
• What happens to pressure if volume increases?

  Pressure decreases
• What is the unit for pressure?

  Newtons per meter squared (Pascals)
• How does altitude affect atmospheric pressure?

  Pressure decreases with higher altitude
• What is the formula for calculating pressure?

  Pressure = Force / Area
• What is weight in physics?

  Force due to gravity acting on an object
• How is weight calculated?

  Weight = Mass × Gravitational field strength
• What is the approximate value of gravitational field strength on Earth?

  9.8 N/kg
• What must be true for forces to be balanced?

  They must add up to zero