Answer :
Final answer:
There are 2.81×10²⁵ calcium atoms in a 187 g sample of calcium, calculated using the molar mass of calcium and Avogadro's number.
Explanation:
The student is asking about the number of atoms in a certain mass of calcium, which is a problem that can be solved using concepts of the mole and Avogadro's number in chemistry. To find the answer, we need to use the molar mass of calcium which is 40.08 g/mol.
To find the number of moles of calcium in 187 g, we divide the mass by the molar mass: (187 g) / (40.08 g/mol) = 4.665 moles of calcium.
Next, we multiply the moles by Avogadro's number (6.02×10²³ atoms/mol) to find the number of atoms:
4.665 moles × 6.02×10²³ atoms/mol = 2.81×10²⁵ atoms of calcium.
Therefore, there are 2.81×10²⁵ calcium atoms in a 187 g sample of calcium.
The important relationship or constant we have to know here is the Avogadro's number. 6.022*10^23 /mole. To answer this, we have to convert the mass of Calcium to moles by dividing it with its molar mass. The molar mass of Calcium is 40 g/mol.
[tex]moles Ca = 187 g * \frac{mol}{40 g} = 4.675 moles Calcium[/tex]
Then we multiply the moles calcium with the Avogadro's constant.
4.675 moles Calcium * 6.022*10^23 /mole = 2.82*10^24 atoms of calcium.
[tex]moles Ca = 187 g * \frac{mol}{40 g} = 4.675 moles Calcium[/tex]
Then we multiply the moles calcium with the Avogadro's constant.
4.675 moles Calcium * 6.022*10^23 /mole = 2.82*10^24 atoms of calcium.
