Molar mass and converting grams to moles
Grade 10 Science Worksheet - Challenge Me
Circle the best answer, or write your answer on the line.
A sample of water (H₂O: 2 H at 1.01 g/mol, 1 O at 16 g/mol) has a mass of 27.03 g. How many moles is it, to 0.01 mol, Esme?
A spoon of water (H₂O: 2 H at 1.01 g/mol, 1 O at 16 g/mol) has a mass of 9.01 g. How many moles is it, to 0.01 mol, Kira?
Noah says one water molecule has a mass of 18.02 g. Which reply fits, Luz?
- Agree: water is light, so 18.02 g fits one drop
- Agree: molar mass is the mass of one molecule
- Disagree: 18.02 g is the mass of a whole mole
Pia says 10 g of salt and 10 g of sugar hold the same number of moles. Which reply fits, Milo?
- Disagree: the sugar holds more moles, as it is heavier
- Disagree: salt's smaller molar mass gives more moles
- Agree: equal grams mean equal moles for any substance
Luz says that to change grams into moles you multiply by 6.022 × 10²³. Which reply fits, Noah?
- Disagree: divide the grams by the molar mass
- Agree, as long as the sample is water
- Agree: Avogadro's number links grams and moles
How many molecules are in 18.02 g of water, Pia?
- 1.085 × 10²⁵ molecules
- 6.022 × 10²³ molecules
- 1 molecule
How many molecules are in 9.01 g of water, Ren?
- 5.426 × 10²⁴ molecules
- 3.011 × 10²³ molecules
- 1.2044 × 10²⁴ molecules
How many molecules are in 88.02 g of CO₂, Tala?
- 5.301 × 10²⁵ molecules
- 3.011 × 10²³ molecules
- 1.2044 × 10²⁴ molecules
Which holds more moles: 10 g of salt or 10 g of sugar, Zee?
- They match, since the masses are equal
- The sugar, since its molar mass is larger
- The salt, since its molar mass is smaller
Which holds more molecules: 18.02 g of water or 44.01 g of CO₂, Ari?
- They match: each is 1 mol
- The water, since its molecules are smaller
- The CO₂, since it has more grams