1.25 g of HClo3 has_____________ molecules (how many) ?
HClO3 is how many moles. moles = g/molar mass.
Then 1 mole of HClO3 contains 6.022E23 molecules.
0.575 moles of Al2(SO4)3 has -------moles of Al3+ ions
36.46 g of HCL has ------------- molecules
To determine the number of molecules in 1.25 g of HClO3, we need to use the concept of molar mass and Avogadro's number.
1. First, we need to determine the molar mass of HClO3. The molar mass of an element or compound is the sum of the atomic masses of all the atoms in its chemical formula.
In this case, HClO3 consists of 1 hydrogen atom (H), 1 chlorine atom (Cl), and 3 oxygen atoms (O). We can find the atomic masses of these elements on the periodic table:
- Hydrogen (H): 1.01 g/mol
- Chlorine (Cl): 35.45 g/mol
- Oxygen (O): 16.00 g/mol
So, the molar mass of HClO3 can be calculated as follows:
Molar mass of HClO3 = (1 × atomic mass of H) + (1 × atomic mass of Cl) + (3 × atomic mass of O)
= (1 × 1.01) + (1 × 35.45) + (3 × 16.00)
≈ 97.46 g/mol
2. After determining the molar mass of HClO3, we can calculate the number of moles in 1.25 g by dividing the given mass by the molar mass:
Number of moles = Mass / Molar mass
= 1.25 g / 97.46 g/mol
≈ 0.0128 mol
3. Finally, to find the number of molecules in the given number of moles, we can use Avogadro's number, which is approximately 6.022 × 10^23 molecules/mol:
Number of molecules = Number of moles × Avogadro's number
≈ 0.0128 mol × 6.022 × 10^23 molecules/mol
≈ 7.72 × 10^21 molecules
Therefore, there are approximately 7.72 × 10^21 molecules of HClO3 in 1.25 g.