a student obtains a sample of a pure solid compound. in addition to avogadro’s number, which of the following must the student know in order to determine how many molecules are in the sample?
a student obtains a sample of a pure solid compound. in addition to avogadro’s number, which of the following must the student know in order to determine how many molecules are in the sample?
Answer: In addition to Avogadro’s number, the student must also know the mass of the pure solid compound in order to determine how many molecules are in the sample.
Avogadro’s number (approximately 6.022 x 10^23) is a fundamental constant that represents the number of molecules, atoms, or entities in one mole of a substance. To calculate the number of molecules in a given sample, you need to use the concept of moles and relate it to the mass of the substance.
The relationship between moles, mass, and Avogadro’s number is given by:
Number of moles = Mass / Molar mass
where:
- Mass is the mass of the substance in grams.
- Molar mass is the mass of one mole of the substance in grams/mole.
Once you have the number of moles, you can then use Avogadro’s number to convert from moles to the number of molecules:
Number of molecules = Number of moles × Avogadro’s number
So, along with Avogadro’s number, knowing the mass of the sample and the molar mass of the compound allows you to calculate the number of molecules in the sample.