Calculate the number of chloride ions (Cl–) in 190.4 g of MgCl2.

Sure, here are the steps to calculate the number of chloride ions in 190.4 g of MgCl2:

1. First, we need to find the molar mass of MgCl2. The atomic mass of Mg is about 24.3 g/mol and Cl is about 35.5 g/mol. Since there are two Cl atoms in MgCl2, the molar mass of MgCl2 is 24.3 g/mol + 2(35.5 g/mol) = 95.3 g/mol.

2. Next, we calculate the number of moles of MgCl2 in 190.4 g. We do this by dividing the mass of the sample by the molar mass of MgCl2. So, 190.4 g ÷ 95.3 g/mol = 2 moles of MgCl2.

3. Now, we need to find the number of moles of Cl- ions. Since there are two Cl- ions for every one molecule of MgCl2, there are 2 * 2 = 4 moles of Cl- ions.

4. Finally, we convert the number of moles of Cl- ions to number of ions using Avogadro's number (6.022 x 10^23 ions/mol). So, 4 moles * 6.022 x 10^23 ions/mol = 2.4088 x 10^24 Cl- ions.

So, there are approximately 2.4088 x 10^24 chloride ions in 190.4 g of MgCl2.