How many moles of ions are released when these samples are dissolved in water?
a. 0.37 mol of NH4Cl
b. 3.55 * 10^18 formula units of
Ba(OH)2 * 8H2O
I need to know what steps to take to get to the answer. Thanks!
0.37 mole NH4Cl dissolved in water will be 0.37 mole NH4Cl. Each mole NH4Cl contains two ions; i.e., NH4^+ and Cl^-. Therefore, 0.37 x 2 = 0.74 mole ions in solution.
thanks
Well, it's a mo-lecular question! Let's break it down step by step, water you waiting for?
For the first one, NH4Cl is a salt that dissociates in water into NH4+ and Cl- ions. Since there is only 1 mole of NH4Cl, there will be 1 mole of NH4+ ions and 1 mole of Cl- ions released.
For the second one, Ba(OH)2 * 8H2O is a hydrate compound. First, we need to find the number of moles of Ba(OH)2. Since there are 8 water molecules per unit, we simply divide the given value by 8. Then, we multiply the resulting moles by 2, as there are 2 moles of OH- ions for each mole of Ba(OH)2. And finally, we multiply by 3 to account for the number of ions in the formula.
So for the second one, step by step:
1. Convert the number of formula units to moles of Ba(OH)2
2. Multiply the moles by 2 to find moles of OH- ions
3. Multiply the moles of OH- ions by 3 to account for the number of ions
I hope these steps have helped you get the answers you were looking for. Just remember, chemistry can be a bit "punny" sometimes!
To determine the number of moles of ions released when a given compound dissolves in water, you need to consider the ions that are formed from the dissociation of the compound.
a. NH4Cl:
NH4Cl dissociates into NH4+ and Cl- ions when dissolved in water. Since the formula of NH4Cl provides one NH4+ ion and one Cl- ion, the number of moles of ions released is equal to the number of moles of NH4Cl. Therefore, the number of moles of ions released is 0.37 mol.
b. Ba(OH)2 * 8H2O:
Ba(OH)2 * 8H2O dissociates into Ba2+ ions and 2 OH- ions per formula unit. However, since you are given the number of formula units, you need to account for this when determining the moles of ions released.
First, calculate the total number of moles of Ba(OH)2 * 8H2O:
Molar mass of Ba(OH)2 * 8H2O = (1 mol of Ba(OH)2 * 8H2O) + (8 mol of H2O)
Molar mass of Ba(OH)2 * 8H2O = (137.33 g/mol) + (8 × 18.015 g/mol)
Molar mass of Ba(OH)2 * 8H2O = 189.339 g/mol
Next, convert the number of formula units to moles:
Number of moles of Ba(OH)2 * 8H2O = (3.55 × 10^18 formula units) × (1 mol Ba(OH)2 * 8H2O / 6.022 × 10^23 formula units)
Number of moles of Ba(OH)2 * 8H2O = 5.88 × 10^-6 mol
Since each formula unit of Ba(OH)2 * 8H2O releases 2 OH- ions, the total number of moles of OH- ions released is:
Number of moles of OH- ions = 5.88 × 10^-6 mol × 2
Number of moles of OH- ions = 1.18 × 10^-5 mol
Therefore, the number of moles of ions released in total is 1.18 × 10^-5 mol of Ba2+ ions and 1.18 × 10^-5 mol of OH- ions.