Mole, avogadro's number and laws of chemical combinations

How many atoms are there in one mole of carbon?

• Avogador's number

• 28000

• 6.022x10^23

• A lot

What is the mass of one mole of carbon atoms?

• 20 g/mol

• 16 g/mol

• 4 g/mol

• 12 g/mol

What is the mass of one mole of carbon dioxide (CO₂)?

C = 12g/mol

O = 16g/mol

• 44 g/mol

• 50 g/mol

• 31 g/mol

• 16 g/mol

How many moles of sodium are there in 250 grams of sodium?

Remember Number of moles = mass / atomic mass

• 10.86 moles

• 10.86 atoms

• 65.45x10^23 atoms

• 6.45 atoms

How many atoms are there in 5.0 grams of gold?

(same formula as before)

• 0.25 atoms

• 0.1528x10^23 atoms

• 0.025 atoms

• none of the above

What is the mass of one mole of water (H2O)?

• 18 g/mol

• 16 g/mol

• 1 g/mol

• 6.022x10^23 atoms

The molar mass of CO₂ is 44.01 g. Therefore, one mole of carbon dioxide has

a mass of _____ , and 0.500 mole has a mass of _____ .

• 40 g and 12.2 g

• 44.01 g and 22.0 g

• 12 g/mol

• 16 g/mol

What is the mass of 6.02 × 1023 atoms of aluminum?

• 1 g/mol

• 27 g/mol

• 20 g/mol

• 13 g/mol

Calculate the definite proportions for H₂O

• 11% of H and 89% of O

• 50% of H and 50% of O

• 20% of H and 80% of O

• 15% of H and 85% of O

Tags

NGSS.MS-PS1-1

Calculate the definite proportions of C₂H₆O

• 52 % of C. 13% of H, 35% of O

• 33.33% of C, 33.3% of H, 33.3% of O

• 50% of C, 50% of O

• 52 % of C. 13% of H, 35% of O