Science 1 Marks Question

The effect of an ant bite can be neutralised by rubbing moist baking soda.

The given liquid sample is acidic in nature. It does not affect red litmus paper, but it turns blue litmus paper red, which is an indication of acidic nature. Also, there is no change in the turmeric indicator, confirming its acidic nature.

Green

Basic

(i) Citric acid
(ii) Tartaric acid

(i) Lemon
(ii) Vinegar

(i) Litmus
(ii) Turmeric
(iii) Beetroot

Lichens

Litmus paper

Neutral substances do not affect the colour of litmus.

Neutralisation

Acids are sour in taste.

A wasp bite injects base into the body. The effect of the injected base can be nullified by applying acid to the infected area. Therefore, it is advisable to apply lemon juice to the affected area because it is an acid.

The reaction between an acid and a base is known as a neutralisation reaction. Salt and water are produced in this process along with the evolution of heat.
Acid + Base → Salt + Water (Heat is evolved.)

Rose petals, when added to warm water, form an extract which is used as an indicator. This indicator turns red in an acidic solution and green in a basic solution.

Take some turmeric powder and mix it in some water to make a paste. Deposit it on blotting paper or filter paper and dry it. Cut thin strips of the yellow paper obtained. These thin strips are turmeric paper.

To prepare lime water, dissolve some lime (calcium oxide, also known as chuna) in water. Stir the mixture and let it sit for a while. Afterward, filter the solution, and the liquid obtained is lime water.

The most commonly used natural indicator is litmus. It is extracted from lichens. It is available in the form of a solution or strips of paper.

Red rose petals extract turns red in an acidic solution and green in a basic solution.

It is because the soap solution is basic, and turmeric acts as a natural indicator that turns red in a basic solution.

The substances which do not show any effect on litmus are called neutral substances.

Acid converts blue litmus into red, while base converts red litmus into blue.

Lichens

Olfactory indicators

The substances that feel soapy to touch and bitter in taste are called bases.

Lemon and tamarind

The substances which are sour in taste are called acids.

Observation and conclusion: Turmeric paper changes colour from yellow to red in a basic solution but shows no change in acidic or neutral solutions.

Observation and conclusion: The rose extract gives a red colour in an acidic solution and a green colour in a basic solution.

Yes, turmeric solution can be used as an indicator for spraying, as it changes colour from yellow to red in basic solutions, while a soap solution could be used for writing on the paper, since soap is basic in nature.

To save the fish in the lake, neutralising the acidic waste by adding a base like lime before releasing it into the water could help restore the neutral nature of water, making it safer for the fish.

People often use natural remedies like applying a paste of baking soda and water, using a cold compress to reduce pain and swelling caused by ant bites.

Yes, there are substances like onion and vanilla extract whose odours change when exposed to acidic or basic substances are known as olfactory indicators.

Yes, there are other natural substances that can be used as acid-base indicators, such as red cabbage juice, turmeric, and rose extract. These substances also change colour in the presence of acids or bases.

Yes, lichens can be found growing on trees, especially in areas with clean air and good rainfall.

 (1) Litmus:It is obtained from lichens.
(2) Red rose:Extracts from red rose petals can be used as an indicator.

Most acids taste is sour.

Lemon juice contains Citric acid.

A neutral solution does not change the color of either red or blue litmus paper.

Some substances whose odours change in an acidic or basic medium. These are called olfactory indicators.

baking soda is a  substance used to neutralise ant bite.

Baking soda solution is basic in nature.

baking soda is a safe to taste.

The colour of turmeric in acidic solution is yellow.

Olfactory indicators are substances that change their smell when mixed with an acidic or basic medium, like onion​.

Basic substances usually feel slippery or soapy when touched, like the baking soda solution​.

If a substance turns blue litmus paper red, it means the substance is acidic in nature​.

Litmus is a natural substance obtained from lichens. It is available as a solution or as paper strips in two colours – blue and red​.

Their white sheets showed the words “Welcome to the Wonderful World of Science” after being sprayed with a liquid. This made them very excited and curious​.