Mole

• What is the definition of a mole in chemistry?

  A mole is a very large number, specifically $6.02 \times 10^{23}$.
• How many carbon atoms are in 12 grams of carbon?

  There are $6.02 \times 10^{23}$ carbon atoms in 12 grams of carbon.
• How many moles of carbon are in 12 grams?

  There is 1 mole of carbon in 12 grams.
• If you have 120 grams of carbon, how many moles do you have?

  You have 10 moles of carbon in 120 grams.
• How many moles are in 1 kilogram of carbon?

  There are approximately 83.3 moles in 1 kilogram of carbon.
• What is the mass of a mole of magnesium?

  A mole of magnesium has a mass of 24 grams.
• How many moles are there in 500 grams of magnesium?

  There are approximately 20.8 moles in 500 grams of magnesium.
• How many moles are in 1 gram of helium?

  There are 0.25 moles in 1 gram of helium.
• Why do chemists prefer to deal with the number of moles?

  Chemists prefer to deal with the number of moles because it represents the number of atoms involved.
• What is the relationship between molar mass and relative atomic mass?

  • The molar mass of a substance is equal to its relative atomic mass in grams.
  • Example: Molar mass of carbon is 12 grams.
  • Example: Molar mass of carbon dioxide is 48 grams.
• How many moles are in 1 gram of lithium?

  There are approximately 0.14 moles in 1 gram of lithium.
• How can you calculate the number of moles from mass?

  You can calculate the number of moles using the formula: $n =$$\frac{m}{M}$, where $n$ is the number of moles, $m$ is the mass, and $M$ is the molar mass.
• What is the triangle used to calculate moles, mass, and molar mass?

  • The triangle consists of:
  • $m$ (mass) at the top
  • $n$ (number of moles) at the bottom left
  • $M$ (molar mass) at the bottom right
  • Use the triangle to rearrange and solve for any variable.
• What should you do when calculating using the periodic table?

  You should use the relative atomic mass from the periodic table to one decimal place.
• What is the significance of the periodic table in chemistry?

  • Provides relative atomic masses of elements.
  • Essential for calculating moles and mass.
  • Helps in understanding chemical reactions and compounds.