Tooth Decay

Q.

How can a farmer convert acidic soil to neutral soil?

Q.

Calcium phosphate is present in tooth enamel, its nature is

1. Acidic

2. Basic

3. Neutral

4. Amphoteric

Q.

The acid present in curd is:

1. Acetic acid

2. Oxalic acid

3. Lactic acid

4. Citric acid

Q.

Why does tooth decay start when the pH of mouth is lower than 5.5 ?

Q.

Question 06.
Calcium phosphate is present in tooth enamel. Its nature is
(a) basic
(b) acidic
(c) neutral
(d) amphoteric

Q.

Rain water with a pH less than 5.6 is called:

1. Neutral rain

2. Basic rain

3. Acid rain

4. Normal rain

Q.

How does tooth enamel get damaged? What should be done to prevent it?

Q.

The acid present in tomato is:

1. Acetic acid

2. Citric acid

3. Oxalic acid

4. Lactic acid

Q. The toothpaste we use is a base but why it can't be acid or neutral?

Q.

The nature of the toothpaste commonly used is Acidic, Neutral, Basic, or baking soda?

Q.

(a) Explain the pH change as the cause of tooth decay. How can we prevent tooth decay caused by pH variations?

(b) Explain how pH change in the lake water can endanger the lives of aquatic animals (like fish). What can be done to lessen the danger to the lives of aquatic animals in the lake?

Q.

While playing in a park, a child was stung by a wasp. Some elders suggested applying the paste of baking soda and other lemon juice as the remedy. Which remedy do you think is appropriate and why?

Q. In acid rain, pH of rain water is:

1. 7
2. more than 9.6
3. below 5.6
4. 9

Q. Antacids such as milk of magnesia have a pH less than 7.

1. True
2. False

Q. Toothpastes are used to prevent tooth decay because they are _______.

1. sweet in taste
2. acidic in nature
3. basic in nature
4. neutral in nature

Q.

Q. What effect do carbonated drinks have on teeth?

1. The teeth will be prone to decay due to sugar content of the drink.
2. It will make the teeth black.
3. It will erode the outer covering of teeth.
4. All of these.

Q. Why does survival of aquatic life becomes difficult because of acid rain?

1. When acid rain falls into the river, it lowers the pH of the river water.
2. None of the above
3. When acid rain falls into the river, it increases the pH of the river water.
4. Acid rain does not cause any change in the river water.

Q. Dinesh is a farmer. He got pH of his soil tested and followed advice of Agricultural Scientists of 'Kissan Centre' in growing crops. He got better quality of crops this year. Answer the following questions.

(i) Why should we get our soil tested?
(ii) If soil has pH less than 7, how can we make it neutral?
(iii) What values are possessed by Dinesh?
[3 Marks]

Q. which acid is present in tomato?

Q. Tooth decay starts when the pH of the mouth is less than:

1. 4.5
2. 6.5
3. 7.5
4. 5.5

Q.

A first aid manual suggests that vinegar should be used to treat wasp Sting and baking soda for bee stings.1 what does this information tell you about the chemical nature of the wasp Stings. 2. If there were no baking soda in the house, what other household substance could you use to treat bee stings?

Q.

Which of the following should be applied in the case of a wasp sting ?

1. Baking soda

2. Vinegar

3. Washing soda

4. Mustard oil

Q. 33.What is a monobasic acid

Q. In mouth, tooth decay occurs when $pH$ is less than _______ .

Q. When pH of rain water is less than 5.6, it is called:

1. monsoon rain
2. acid rain
3. basic rain
4. heavy rain

Q. Calcium phosphate is present in tooth enamel, its nature is:

1. basic
2. acidic
3. neutral
4. none of the above

Q. What is $pH$ Scale? Explain that $pH$ change of the mouth is the cause of tooth decay.

Q. How is tooth decay related to $pH$? How can it be prevented?

Q. To protect tooth decay we are advised to brush our teeth regularly. The nature of the tooth paste commonly used is:

1. acidic
2. basic
3. neutral
4. corrosive