Dichloroethane a compound that's often used for dry cleaning, contains carbon, hydrogen and chlorine. it has a molar mass of 99g/mol. Analysis of sample shows that it contains 24.3%carbon and 4.1%hy?

To find the percentage of chlorine in dichloroethane, we can first calculate the percentage of hydrogen in the compound.

First, we need to find the percentage of carbon in the compound:
24.3% carbon = 24.3g C / 12.01g/mol = 2.02 mol C

Next, we can calculate the percentage of hydrogen in the compound:
4.1% hydrogen = 4.1g H / 1.01g/mol = 4.06 mol H

Now, we can calculate the total molar mass contributed by carbon and hydrogen:
Total molar mass = (2.02 mol C x 12.01 g/mol) + (4.06 mol H x 1.01 g/mol) = 32.48 g/mol

To find the molar mass contributed by chlorine:
Molar mass of chlorine = 99 g/mol - 32.48 g/mol = 66.52 g/mol

Finally, we can calculate the percentage of chlorine in the compound:
Percentage of chlorine = (66.52 g/mol / 99 g/mol) x 100% = 67.2%

Therefore, dichloroethane contains 67.2% chlorine.

Step 1: Determine the empirical formula

- Convert the percentages to grams:

```
Carbon: 24.3 g
Hydrogen: 4.1 g
```

- Find the number of moles of each element:

```
Carbon: 24.3 g / 12.01 g/mol = 2.02 mol
Hydrogen: 4.1 g / 1.01 g/mol = 4.06 mol
```

- Divide each number of moles by the smallest number of moles (2.02 mol):

```
Carbon: 2.02 mol / 2.02 mol = 1
Hydrogen: 4.06 mol / 2.02 mol = 2
```

- Thus, the empirical formula is CH2.

Step 2: Determine the molecular formula

- The molar mass of the empirical formula (CH2) is 14 g/mol.
- The molar mass of the compound is 99 g/mol.
- Divide the molar mass of the compound by the molar mass of the empirical formula:

```
99 g/mol / 14 g/mol = 7
```

- Thus, the molecular formula is (CH2)7 or C7H14.

Therefore, the molecular formula of dichloroethane is C7H14.