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# Are all compounds that contain hydrogen not an acid?

Acids and bases play an important role in our lives and the environment around us, from our bodies to our planet’s oceans and rocks. You’ve encountered acids and bases if you’ve ever tasted lemon juice or washed your hands with soap. Scientists categories substances as acids, bases (also known as alkali), or neutral based on properties such as taste and pH.

### Identifying Acids and Bases

A pH meter determines whether a solution is acidic or basic. When we use a pH meter to test a substance, we get a number between 0 and 14. This is a pH scale that can be used to compare different substances. This means that a pH scale decrease of one can result in a tenfold increase in hydrogen ion concentration.

Acids have a pH of less than 7. The higher the concentration of H+ ions, the more acidic the solution and the lower the pH. Bases have a pH greater than 7. pH 7 is considered neutral, indicating a balance of H+ and OH ions. For very strong acids, the pH value can be less than 0 and for very strong bases, it can be greater than 14.

### Experiment To Show That All the Compounds Containing Hydrogen are Not Acids

Insert two nails into the wooden or rubber cork and place it in a beaker. Using a wire, connect these iron nails to a bulb, a 6-volt battery, and a switch. Pour some alcohol or glucose into a container large enough for the nails to dip into. When you turn the switch on, you will notice that the bulb does not light up. Now, empty the beaker and add some HCl aqueous solution; the bulb should glow at this point. This demonstrates that acid can conduct electricity while alcohols and glucose cannot, even in the presence of hydrogen.

### Experiments based on the property of acids and base

• Litmus Test

Litmus is the most widely used natural indicator, and it is available in the form of strips of paper or a solution. It is derived from lichens. When an acidic solution is added, it turns red, and when a basic solution is added, it turns blue.

• Copper Coin Experiment

Pour a small amount of a liquid solution into each of a few different cups. Try a few different solutions that you know are acidic and a few that you know are basic. All that remains is to drop the copper coins into the solution. You can lay them flat in the bottom of the cup, but the results will be more drastic if you stand the coin on end so that only half of it gets soaked in the liquid. The acids will dissolve the tarnish on the copper coins, restoring them to their original gleaming state.

• Raw Egg Experiment

Put a raw egg in a vinegar bath to soften it. The highly acidic vinegar dissolves the shell, effectively transforming it into an acid-cooked soft-boiled egg. If you drop it carefully, it will even bounce. It also demonstrates that How a chemical reaction between the acetic acid in vinegar and calcium carbonate in eggshell results in a rubbery egg?

### Sample Questions

Question 1: Distinguish between acid and a base.

When an acid is added to water, it produces hydrogen (H+) ions, whereas a base is a substance that neutralises acids. When bases are added to water, they split to form hydroxide ions, which are denoted by the symbol OH. An alkaline solution is a base solution that has been added to water.

Question 2: How will you identify acid or base with the help of the pH scale?

A pH metre determines whether a solution is acidic or basic. When we use a pH metre to test a substance, we get a number between 0 and 14. This is a pH scale that can be used to compare different substances. Acids have a pH less than 7, while bases have a pH greater than 7. pH 7 is considered neutral.

Question 3: How does the litmus test identify acid and base?

Litmus is the most widely used natural indicator, and it is available in the form of strips of paper or a solution. It is derived from lichens. When an acidic solution is added, it turns red, and when a basic solution is added, it turns blue.

Question 4: What is the purpose of the raw egg experiment?

A raw egg experiment is intended to show how a chemical reaction between acetic acid in vinegar and calcium carbonate in the egg shell results in a rubbery egg.

Question 5: Define olfactory indicators. Give two examples of substances that can be used as olfactory indicators.