a sample of silver nitrate agno3 is has a mass of 255.4g. How many particles (formula units) of silver nitrate are present in the sample

Question

 a sample of silver nitrate agno3 is has a mass of 255.4g. How many particles (formula units) of silver nitrate are present in the sample

Answer 1

Hi Meka,

 

So in class, you've probably learned about Avagadro's number (6.02 x 10^23). This number states how many atoms/molecules are within a particular mole of said substance. So in order to find the number of particles of silver nitrate present, first we need to find how many moles of silver nitrate we have. 

 

So, we divide the mass of the silver nitrate sample by its molar mass, which we don't have.

 

We can find the molar mass of silver nitrate by adding the molar masses of each of the atoms that make up the molecule (the one atom of silver, one atom of nitrogen, and three atoms of oxygen). This is the molar mass of the silver nitrate compound.

 

To get the number of moles in the sample, we divide the mass of the sample by the molar mass we just found. Then multiply the number of moles by Avagadro's number to yield the number of particles in the sample.

 

Hope this helped!