Advertisements
Advertisements
Question
The indicator which produces a pink colour in an alkaline solution is ______.
Options
methyl orange
turmeric paper
phenolphthalein
litmus paper
Advertisements
Solution
The indicator which produces a pink colour in an alkaline solution is phenolphthalein.
Explanation:
Phenolphthalein is a synthetic chemical indicator that is highly sensitive to changes in pH levels. In neutral or acidic environments, the compound remains completely colourless. However, when introduced to an alkaline (basic) solution with a pH rising above 8.2, its molecular structure alters, causing it to produce a vivid pink colour. Conversely, methyl orange turns yellow, turmeric paper turns reddish-brown, and litmus paper turns blue in basic media.
APPEARS IN
RELATED QUESTIONS
Name the gas evolved when dilute HCl reacts with sodium hydrogencarbonate. How is it recognised?
What colour does phenolphthalein indicator turn when added to an alkali (such as sodium hydroxide)?
What is the common name of water soluble bases?
What happens during a bee sting? What is its remedy?
Why is it wrong to treat a bee sting with vinegar?
What type of ions are formed?
When an acid is dissolved in water.
What happens when bases react with non-metal oxides? Explain with the help of an example. What does this reaction tell us about the nature of non-metal oxides?
Wasp sting contains ______.
The acid produced naturally in our stomach is ______.
Give one example in the following case:
A hydrogen containing compound which is not an acid.
Write balanced equation to satisfy the following statement:
\[\ce{Acid + Carbonate or bicarbonate -> Salt + water + Carbon dioxide}\]
Write balanced equation to satisfy the following statement:
\[\ce{Acid + Sulphite or bisulphite -> Salt + water + sulphur dioxide}\]
What do you understand by the strength of an acid? On what factors does the strength of an acid depend?
Fill in the blank
The word acid comes from latin word acidus meaning _________
In acidic solutions blue litmus changes into ______ colour.
Match the acids given in column (A) with their correct source given in column (B)
| Column (A) | Column (B) |
| (a) Lactic acid | Tamarind |
| (b) Acetic acid | Lemon |
| (c) Citric acid | Vinegar |
| (d) Tartaric acid | Curd |
Acids are ______ in taste.
Complete the following equation.
ZnO + 2HCl → ______ + ______.
Which one of the following will not produce an acid when made to react with water.
