Everything has mass even if it is air or vapor. Every solution is a mixture of two or more components. Most of these solutions either occur naturally or are obtained through experiments. Various types of acids are used in households and experimentation processes. Naturally occurring acids and some man-made acids are used in our daily lives. Talking about acid today, I just wonder what is the mass percent of chlorine in Hydrochloric Acid. How do you find the mass percent of chlorine? What is the percentage of hydrogen in Hydrochloric Acid? Let’s begin and find it out.

**1. What is Hydrochloric Acid?**

An **aqueous solution of hydrogen chloride** is known as Hydrochloric Acid (HCL) or muriatic acid. It is also found as a component in the gastric acid that is found in the digestive systems of various animal species, including humans. Yes, Hydrochloric Acid is produced commercially by dissolving gaseous hydrogen chloride in water, and it occurs naturally inside your body. (See How Acidic Is Stomach Acid?)

**2. What are the Chemical Properties of Hydrochloric Acid?**

- Gaseous hydrogen chloride is a molecular component that has a covalent bond between the chlorine and hydrogen atoms.
- Theoretically, the pKa value of hydrochloride acid in an aqueous solution is estimated to be -5.9.
- Dissolved hydrogen chloride in water makes a strong acid.
- Effectively, the concentration of Hydrochloric Acid (HCL) is zero.

**3. What are the Physical Properties of Hydrochloric Acid?**

This simple chlorine-based acid has the following physical properties:

- It is the least hazardous acid to handle.
- It is non-toxic and has non-reactive chloride ions.
- Boiling and melting points depend on the concentrations of Hydrochloric Acid.
- It is colorless.
- It has a pungent odor.
- It is very stable.
- It has the capacity to maintain its concentration.

**4. What is Mass Percentage Composition?**

Before moving ahead to know the mass percent of chlorine in Hydrochloric Acid, it is better to understand its definition and formula. It tells you the percentage of each element that is present in a compound. There can be two or more elements in a chemical compound. It helps to calculate the **percentage composition of the molar mass of an element compared to the total composition**. With the following formula, you can easily find out the concentration percentage of any element in a compound.

The mass percent of an element = (Mass of the element in 1-mole compound / Molar mass of Compound) × 100%. (See What are the Characteristics of an Element?)

**5. How to Find the Mass Percentage of an Element?**

With the following steps, you can solve and find out the percentage of a particular element in a compound.

**Step 1: Finding the Molar Mass of an Element**

Begin with finding the molar mass of all the elements present in the compound. For example, in Hydrochloric Acid, there are two elements: hydrogen and chlorine. You will find out the molar mass of those two. The same rule applies to another compound no matter how many elements it has. **Molar mass is the weight of the element**. The atomic mass is converted into grams per mol for this. For example, if the atomic mass of an element is 1, its molar mass will be 1 gram/mol.

**Step 2: Finding the Molar Mass of compound**

It is another step that will help you in finding the mass percent of chlorine in Hydrochloric Acid. After getting the molar mass of each element you need to know the mass of the entire compound. Like here you got the molar mass of chlorine and hydrogen, now, you need to find out the molecular mass of Hydrochloric Acid (HCL) as a whole. This is done by adding the molar masses of all the elements.

**molar mass of element #1 + molar mass of element #2 = Molar mass of compound.
**For example, the molar mass of hydrogen + molar mass of chlorine = Molar mass of Hydrochloric Acid

**Step 3: Divide**

Next, you will be dividing the **molar mass of the element by the molar mass of the compound**. The element here mentioned is the one whose percentage you need to find. After division, the answer will be between 0 and 1, in decimals.

**Step 4: Multiply**

The last step is to **multiply the result obtained by dividing by 100.** The answer will be in decimal with lots of digits after the decimal point. You have to round it off, and you will get the answer. (See How many Oxygen Atoms are in SiO2)

**6. How do you Find the Mass Percent of Chlorine?**

If you are looking for a way to find the mass percent of chlorine in Hydrochloric Acid, you can simply do this as mentioned here.

**Mass Percent = (Mass of the element in 1-mole compound / Molar mass of compound) × 100%**

Here, first, you have to find the molar mass (at. weights) of the elements i.e. H and Cl, and then add them to get the total molar mass,

- The molar mass of Hydrogen is 1.008 g/mol.
- The molar mass of chlorine is 35.5 g/mol.
- Mass of Hydrochloric Acid (HCL) = 35.5 grams/mol + 1.008 grams/mol = 36.5 grams/mol [rounded off].

Now, we will apply the formula for finding the percentage of an element in the compound,

According to the question you need to find the mass percent of chlorine, therefore, in place of the element, we will write the mass of chlorine. Then it needs to be divided by the molecular mass which will be the total mass of the Hydrochloric Acid (HCL).

- Mass percentage of chlorine = (Molar Mass of chlorine/ Molar mass of Hydrochloric Acid) × 100
- Mass percentage of chlorine = (35.5 grams per mol / 36.5 grams per mol)
**×**100% - Mass percentage of chlorine = 0.9726
**×**100% = 97.26% [rounded off]

Therefore, the mass percent of chlorine in Hydrochloric Acid is **97.26%**. (See What is the Number in Periodic Table of Elements H2O?)

**7. What is the Mass Percent of Chlorine in Hydrochloric Acid?**

We know that the atomic mass of hydrogen is 1.008u and chlorine is 35.5u. With the process applied above, we came to the conclusion that the mass percentage of the element chlorine in the compound Hydrochloric Acid is **97.26%. **(See How does Calcium Chloride react with Chlorine?)

**8. What is the Percentage of Hydrogen in Hydrochloric Acid?**

Image by Gerd Altmann from Pixabay
To find the mass percent of hydrogen in Hydrochloric Acid, you can simply do this as mentioned here.

**Mass Percent = (Mass of the element in 1-mole compound / Molar mass of compound) × 100%**

Here, first, you have to find the molar mass (at. weights) of the elements i.e. H and Cl, and then add them to get the total molar mass,

- The molar mass of Hydrogen is 1.008 g/ mol.
- The molar mass of chlorine is 35.5 g/ mol
- Molar mass of Hydrochloric Acid (HCL) = 35.5 grams/mol + 1.008 grams/mol = 36.5 grams/mol [rounded off]

Now, apply the formula for finding the percentage of hydrogen in the compound,

According to the question you need to find the percentage of hydrogen, therefore, in place of the element, we will write the mass of hydrogen. Then it needs to be divided by the molecular mass which will be the total mass of the Hydrochloric Acid (HCL).

- Mass percentage of hydrogen = (Molar Mass of hydrogen/ Molar mass of Hydrochloric Acid) × 100
- Mass percentage of hydrogen = (1.008 per mol/36.5 grams per mol)
**×**100% - Mass percentage of hydrogen = 0. 02761
**×**100% = 2.76% [rounded off]

Therefore, the mass percentage of hydrogen in Hydrochloric Acid is ** 2.76%.**

So, with this, you found the percentage of hydrogen in Hydrochloric Acid. The process of finding how do you find the mass percent of chlorine or any other element of a compound is the same if you follow the steps carefully. If you find this piece informative, share it with your friends and let them brush up on topics like finding the mass percent of chlorine in Hydrochloric Acid, the percent of hydrogen in it, etc. (See 14 Sodium Facts: What is Sodium Made of?)