2. amount of substance

• What is Avogadro's number?

  $6.02 \times 10^{23}$
• What does one mole of any substance contain?

  Avogadro's number of atoms or molecules
• How do you calculate the number of particles in a substance?

  Multiply Avogadro's number by moles
• How many particles are in 0.67 moles of ammonia?

  $4.02 \times 10^{23}$
• What is the formula to calculate the number of moles using mass?

  Number of moles = mass / Molar mass
• How do you calculate the number of moles in 23 g of gold?

  Divide 23 g by 197 g/mol
• What is the atomic mass of gold?

  197 g/mol
• What should you do if you have two components in a question regarding moles?

  Use the moles formula to calculate
• How can you calculate moles in a solution?

  Using concentration and volume
• What is the formula for calculating moles from concentration and volume?

  Number of moles = concentration × volume
• What must the volume be in when calculating moles from concentration?

  Decimeters cubed
• How do you convert cm cubed to dm cubed?

  Divide by 1000
• How many moles are in 200 cm cubed of 0.35 moles per dm cubed HCl?

  0.07 moles
• What is the ideal gas equation?

  PV = nRT
• What does 'R' represent in the ideal gas equation?

  The gas constant
• What units must pressure be in for the ideal gas equation?

  Pascals
• How should volume be measured in the ideal gas equation?

  In meters cubed
• How do you convert temperature from Celsius to Kelvin?

  Add 273
• What is the volume of 0.36 moles of gas at 100 kPa and 298 K?

  $8910 \text{ cm}^3$
• What is the standard condition for temperature in gas calculations?

  298 Kelvin
• What is the standard pressure in gas calculations?

  100 kilopascals
• What are the conversions between meters, decimeters, and centimeters?

  • 1 meter = 10 decimeters
  • 1 decimeter = 10 centimeters
  • 1 meter = 100 centimeters
• How do you convert between different volume units?

  • From m³ to dm³: multiply by 1000
  • From dm³ to cm³: multiply by 1000
  • From m³ to cm³: multiply by 1,000,000
• What is the significance of significant figures in calculations?

  • Indicates precision of measurements
  • Important for accuracy in scientific calculations
  • Must be maintained throughout calculations
• What should you do if in doubt during calculations?

  • Work out the number of moles
  • Use known values to find other variables
  • Check previous calculations for accuracy
• How do you convert meters to decimeters?

  Multiply by 100
• Why do we multiply by 100 when converting from meters to centimeters?

  There are 100 centimeters in a meter
• What is the conversion factor from meters to centimeters?

  Multiply by 100
• How do you convert square meters to square decimeters?

  Multiply by 10,000
• What is the conversion factor from cubic meters to cubic decimeters?

  Multiply by 1,000,000
• What are spectator ions in an ionic equation?

  They do not participate in the reaction
• What is the general formula for state symbols in chemistry?

  S for solid, L for liquid, G for gas, AQ for aqueous
• How do you calculate theoretical mass from a balanced equation?

  Use molar ratios from the equation
• How do you find the number of moles from mass and atomic mass?

  Divide mass by atomic mass
• What is the ideal gas equation used for calculating gas volumes?

  PV = nRT
• What does the variable 'R' represent in the ideal gas equation?

  The gas constant
• How do you convert pressure from kilopascals to pascals?

  Multiply by 1,000
• What is the purpose of titration in chemistry?

  To determine the concentration of a solution
• What is the endpoint in a titration?

  The point where the indicator changes color
• How do you ensure accurate readings from a burette?

  Read at eye level and at the bottom of the meniscus