What is PH Class 10 ?

`P^H` plays an important role in our daily life. All organisms are `P^H`-sensitive. The human body functions within a range of `P^H` of 7.0  to 7.8 and `P^H` also plays a significant role in the medical field, agriculture, and industries.

In this article, we will discuss a detailed explanation of the definition of the `P^H`, `P^H` scale, `P^H` formula, its uses, and the importance of `P^H` in everyday life.

Table of Contents

    1.  What is P^H definition in chemistry?

    2.  What is the P^H scale?

    3.  Relation between `P^H` and hydrogen ion concentration

    4.  Write the importance of P^H in everyday life class 10

    5.  List of `P^H` values of different substances

    6.  Quizon `P^H`

    7.  Importantquestions on `P^H`

    8.  FAQs

 

1.   What is the `P^H` definition in chemistry?

In `P^H`, P stands for ‘Potenz’ which means power and H stands for hydrogen ions.

PH is a negative logarithm of the concentration of hydrogen ions.

      `P^H= -log_10[H^+]`

We know hydrogen ions are not present in solution, they combine with water and form hydronium ions.

      `H^+   +  H_2O\rightarrow  H_3O^+`

So PH value can be written

       `P^H= -log_10[H_3O^+]`

 

2.   What is the `P^H` scale?

The scale that is used to measure the `P^H` of any solution is known as the `P^H` scale. This `P^H` scale was first made by Sorenson in 1909.

This scale is used to find the concentration of `H^+` or `OH^-` ions present in the solution.

The `P^H` scale has range from 0 to 14. Actually, a universal indicator, a mixture of several indicators shows different colours at different concentrations of `H^+` ions in a solution.

 a). PH =below 7 – Acidic nature

 b). PH = 7 – Neutral

 c). PH= above 7- Basic nature

PH scale

 3.    Relation between `P^H` and hydrogen ion concentration

The strength of acids and bases depends on the concentration of hydrogen ions according to Arrhenius theory.

The more hydrogen ions concentration shows its lower PH value and the solution is acidic.

On the other hand, the more hydroxyl ions concentration [low `H^+` ions] shows its higher PH value and the solution is basic.

4.   Write the importance of `P^H` in everyday life class 10

The human body, animals, plants, and soil all function well in a definite range of `P^H`. following are the problems based on `P^H`.

i.    Acidity in the stomach

ii.  Tooth decay

iii.  Sting of insects

iv.  Acid rain

v.    `P^H` of soil

i.  Acidity in the stomach

   Stomach secret hydrochloric acid which helps in proper digestion but sometimes we face indigestion and acidity. At this time excess HCl is produced and the `P^H` of the stomach decreases. This causes pain and burning in the stomach.

To get rid of it, an antacid which is a mild base like magnesium hydroxide (milk of magnesia `Mg(OH)_2)` is used.

As `P^H`  increases, acidity in the stomach gets cured.

ii.   Tooth decay

`P^H` of mouth is almost 6.5. bacteria present in the mouth reduce the `P^H` of the mouth when they react with food particles and produce acid.

Tooth enamel is made up of calcium phosphate which hardest substance but it gets corroded when `P^H` becomes lower than 5.5, so a decrease in `P^H` causes tooth decay.

To prevent tooth decay, we must clean our teeth after taking a meal and use toothpaste or an alkaline solution to neutralize it.

iii.  Sting of insects

Insects like the honeybee, ant when biting us, they release acid that causes pain and burning. If we use sodium hydrogen carbonate on that part, it neutralizes and we feel relief.

iv.   Acid rain

Rain water is pure but due to the presence of pollutants like `SO_2`, `NO_2`, and other, its `P^H`  decreases. This is called acid rain.

Acid rain affects rivers and soil and monuments. Acid rain affects the whole ecosystem.

To control acid rain, we must control pollutants.

v.   `P^H` of soil

Different soil has different `P^H` values. The `P^H` level of the soil directly affects the soil and the availability of essential nutrients for the plant.

If a plant is placed in the wrong kind of soil then its growth will be affected due to lacking nutrients. So plants should be placed after determining the P^H of the soil. The `P^H` of soil can be measured through simple methods and soil can be treated.

5.  List of `P^H` values of different substances

Following is the list of `P^H` values of different substances

 

Substance/solution	`P^H` Value	Nature
Saliva	6.5 to 7.5	Neutral
Lemon juice	2.2 to 2.4	Acidic
Carrot juice	6.4 to 6.6	Acidic
Coffee	4.5 to 5.5	Acidic
Tomato juice	4.1	Acidic
Tap water	6.9 to 7	Neutral
1MNaOH	14	Basic
1M HCl	0	Acidic
Gastric juice	1.2	Acidic
Distilled water	7	Neutral
Milk of magnesia	10	Basic
Human blood	7.4	Basic

  

6. Quiz on `P^H`

7. Important questions on `P^H`

Q1. How can we measure the exact `P^H` of a solution?

Ans.- Exact P^H can be measured by a `P^H` meter.

Q2.Does the Universal indicator give exact P^H?

Ans. – No, it can give only a rough idea about the `P^H` of the given solution.

Q3. What is the range of the `P^H` scale?

Ans . – From 0 to 14

Q4. Where are bases found on the P^H scale?

  Ans. – The P^H scale range is from 0 to 14 and all bases are found above 7 on the pH scale. An increase in the `P^H` value shows an increase in the concentration of hydroxyl ions which shows the substance is a base.

Q5. How does the `P^H` scale work?

  Ans. –  The `P^H` scale ranges from o to 14 and is based on the concentration of hydrogen ions in the solution. A value below 7 indicates acidic nature, a value of 7 indicates neutral nature and a value above 7 indicates the basic nature of the solution.

 

Related Topics

1. What happens during a chemical reaction

8. FAQs

1.  What does the P^H scale measure the concentration of?

 Ans. – The P^H scale measures the concentration of hydrogen ions present in the solution and shows the acidity or alkalinity of the solution.

2.  What number is neutral on the `P^H` scale?

Ans. – The `P^H` scale range lies between 0 and 14, the number 7 is for neutral substance on it.

3.  What is the strongest acid on the ph scale?

 Ans. – `P^H` value 0 [zero] represents the highest concentration of hydrogen ions and the highest hydrogen concentration means the substance is a strong acid.

4.  Who invented the `P^H` scale?

Ans. – Sorenson invented the `P^H` scale.

5.  What is the relationship between the P^H scale and concentration?

Ans.- The concentration of hydrogen ions increases, The `P^H` value decreases, and vice versa.

6.  On the `P^H` scale, which number has the highest concentration of hydrogen ions? 

 Ans.- The `P^H` value 0 has the highest hydrogen concentration on the `P^H` scale.

7.  What is the highest base on the `P^H` scale?

Ans. – The substance with the `P^H` value is the highest or strongest base.