How many molecules are there in 6.8 grams of CO2
mols = g/molar mass
To determine the number of molecules in a given mass of substance, we need to use the concept of molar mass and Avogadro's number.
Step 1: Calculate the molar mass of CO2.
CO2 consists of one carbon atom (C) with an atomic mass of approximately 12.01 grams per mole and two oxygen atoms (O) with an atomic mass of approximately 16.00 grams per mole.
Molar mass of CO2 = (1 * 12.01 g/mol) + (2 * 16.00 g/mol) = 44.01 g/mol
Step 2: Determine the number of moles of CO2 in 6.8 grams.
Number of moles = Mass / Molar mass
Number of moles = 6.8 g / 44.01 g/mol ≈ 0.1545 mol
Step 3: Calculate the number of molecules.
Avogadro's number tells us that 1 mole of any substance contains 6.022 x 10^23 particles (molecules, atoms, or ions). Therefore, the number of molecules in 0.1545 moles of CO2 is:
Number of molecules = Number of moles × Avogadro's number
Number of molecules = 0.1545 mol × 6.022 x 10^23 molecules/mol ≈ 9.29 x 10^22 molecules
So, there are approximately 9.29 x 10^22 molecules in 6.8 grams of CO2.