Amount of substance

• What are the products in the reaction between a metal and an acid

  Salt and hydrogen
• What are the products in the reaction between an acid and an alkali

  Salt and water
• What are the products in the reaction between an acid and carbonate

  Salt and water and carbon dioxide
• What are the products in the thermal decomposition of a metal carbonate

  Metal oxide and carbon dioxide
• What are the products of complete combustion

  Carbond dioxide and water
• What are the products of the reaction of a metal and oxygen

  Metal oxide
• What is avogadros constant

  6.02×10²³
• What is a mole

  The amount of substance that contains the same number of particles as there are atoms in 12g of carbon 12 (avogadros constant)
• What is the definition of relative atomic mass

  The average mass of one atom of an element compared to 1/12 the mass of one atom of carbon 12
• What is the definition of relative molecular mass

  The average mass of one molecule compared to 1/12 the mass of one atom of carbon 12
• What does yield refer to

  The amount of product obtained in a chemical reaction
• Why is yield never 100%

  • The reaction may nor have gone to completion
  • Other reactions (side reactions) may have taken place along side the main reaction
  • Purification of the product may result in the loss of some product
• Define theoretical yield

  The maximum mass of a product that can be made
• Define actual yield

  How much product is actually obtained
• What is the equation for percentage yield

  Percentage Yield = actual yield/theoretical yield ×100%
• What is atom economy

  A measure of the amount of starting materials that end up as useful products
• What is the equation for percentage atom economy

  % atom economy = mass of desired product/total mass of products ×100
• What is the equation involving moles volume and molar gas volume

  Moles (mol) = V (dm³) × 24 (dm‐³ mol‐¹)
• What are standard conditions

  298k, 101kPq
• What is 1 litre the same as

  1 dm³
• What is the equation including moles, number of particles and avogadros constant

  Moles = number of particles/ avogadros constant
• What is the ideal gas equation and what are the units

  PV = nRT

  Pressure - Pa

  Volume - m³

  Moles - mol

  Temperature - K (+273)

  Gas constant - 8.32 J mol‐¹ K‐¹
• How to get from dm³ to m³

  ÷1000
• How to get from cm³ to m³

  ÷1000000
• How to get from kPa to Pa

  ×1000
• How to get from MPa to Pa

  ×1000000
• Equation for concentration

  Concentration(g/dm^3) = moles(mol)/volume(dm³)
• How can a bas be considered an alkali

  If it is soluble
• What are the 3 types of bases

  • Metal oxides
  • Metal hydroxides
  • Metal carbonates
• What is the purpose of a titration

  Used to determine concentrations of a substance, by working out how much of that substance reacted with another, of known concentration and volume
• Why do we use a burette

  Allows us to measure varying volumes of liquid on a small scale
• How can we ensure repeatable and accurate results

  1. Read from bottom of meniscus, 2d.p and eye level
  2. Remove air bubbles from burette
  3. White tile - easily see end point
  4. Repeat titrations - concordant results
  5. Rinse conical flask with water (acid)
  6. Rinse burette and pipette with reagent
  7. Remove funnerl from top of burette - may change volume reading
  8. Rinse all splashes in conical flask with distilled water
• Method of titration

  • Fill burette with base
  • Graduated pipette - measure 25cm³ of acid - fill conical flask
  • Add a few drops of phenolphthalein into acid
  • Record initial volume of burette
  • Add base into acid from burette (titrate) . Near end point Add base drop wise until colour persists
  • Record end volume of burette
  • Rinse conical flask with distilled water
  • Repeat until concordant results
• Equation for percentage uncertainty

  Percentage uncertainty = absolute uncertainty/measured value ×100%
• What is uncertainty from pipette

  ±0.05 cm³
• What is total uncertainty from burette

  ±0.15cm³
• How to work out total percentage error for a titration

  [0.05/25.00 + 0.15/titre] × 100%
• What is the endothermic reaction for hydrated copper sulfate into its products

  CuSO4•5H2O -->CuSO4 + 5H2O

  Blue --> white
• Method to find practically the formula of a hydrated crystal

  1. Find the mass of an empty boiling tube. Record this and all other masses in a suitable table
  2. Place about 2cm depth of hydrated magnesium sulfate in the boiling tube and find the mass
  3. Heat the tube to constant mass
• What is the definition for empirical fomula

  Shows the simplest whole number ratio of atoms of each element in a substance