You are provided with a compound composed of 22.2%zinc,11.6%sulphur,22.3%oxygen and the rest percentageis water of crystallization.calculate the molecularformula atthecompoundifits molecularmassis161?

To find the molecular formula of the compound, we first need to determine the empirical formula based on the percentages of each element present.

1. Convert the percentages to moles:
- Zinc (Zn): 22.2%
- Sulphur (S): 11.6%
- Oxygen (O): 22.3%
- Water (H2O): 100% - (22.2% + 11.6% + 22.3%) = 43.9%

2. Calculate the moles of each element:
- Zinc (Zn): 22.2g / 65.38 g/mol = 0.34 mol
- Sulphur (S): 11.6g / 32.06 g/mol = 0.36 mol
- Oxygen (O): 22.3g / 16.00 g/mol = 1.39 mol
- Water (H2O): 43.9g / 18.02 g/mol = 2.44 mol

3. Determine the mole ratio of each element:
- Zinc (Zn): 0.34 / 0.34 = 1
- Sulphur (S): 0.36 / 0.34 ≈ 1
- Oxygen (O): 1.39 / 0.34 ≈ 4
- Water (H2O): 2.44 / 0.34 ≈ 7

4. Find the simplest whole number ratio:
- Zinc (Zn): 1
- Sulphur (S): 1
- Oxygen (O): 4
- Water (H2O): 7

5. Write the empirical formula: ZnSO4.7H2O

6. Calculate the molar mass of the empirical formula:
- ZnSO4: (65.38 + 32.06 + 4*16.00) = 161.44 g/mol
- 7H2O: 7*(2*1.01 + 16.00) = 126.14 g/mol
- Total molar mass: 161.44 + 126.14 = 287.58 g/mol

7. Determine the molecular formula:
- Molecular mass given: 161 g/mol
- Molecular mass of empirical formula: 287.58 g/mol
- Molecular formula: (161/287.58) * ZnSO4.7H2O = ZnSO4.4H2O

Therefore, the molecular formula of the compound is ZnSO4.4H2O.

Step 1: Calculate the empirical formula

The empirical formula represents the simplest whole number ratio of elements in a compound. To determine the empirical formula, we need to find the moles of each element present:

- Moles of Zn = (22.2 g / 65.4 g/mol) = 0.339
- Moles of S = (11.6 g / 32.1 g/mol) = 0.361
- Moles of O = (22.3 g / 16.0 g/mol) = 1.39

Dividing each by the smallest number of moles (0.339):

- Zn: 0.339 / 0.339 = 1
- S: 0.361 / 0.339 = 1.065 ≈ 1
- O: 1.39 / 0.339 = 4.1

Rounding off to the nearest whole numbers, the empirical formula is approximately ZnSO₄.

Step 2: Determine the number of empirical formula units in the molecular formula

Molecular mass = 161 g/mol
Empirical formula mass of ZnSO₄ = 65.4 + 32.1 + 4(16) = 161 g/mol

Therefore, the number of empirical formula units in the molecular formula = 161 g/mol / 161 g/mol = 1

Step 3: Write the molecular formula

The empirical formula is ZnSO₄, and there is one empirical formula unit in the molecular formula. Therefore, the molecular formula is:

ZnSO₄