CBSE Class 10 Science 2017 · Paper 31(B)/C · Question 34
What material do you use to prepare soap in the laboratory ? How would you test the nature (Acidic / Basic) of the reaction mixture ?
Answer
Vegetable oil and sodium hydroxide solution (with common salt to separate the soap); red litmus turning blue shows the mixture is basic.
Material: a vegetable oil (for example castor, cottonseed or coconut oil) and sodium hydroxide solution (about 20%), warmed and stirred together; common salt is added afterwards to make the soap separate out.
Test: put a drop of the reaction mixture on red litmus paper and on blue litmus paper. The red litmus turns blue and the blue litmus stays blue, so the reaction mixture is basic.
🔒 Step-by-step solution
Sign up free to see every step of how it is worked out.
From the board paper
More questions from Carbon and its Compounds
Class 10 Science — every question with an expert-verified, step-by-step solution.
- Q1 Ethane, with the molecular formula C₂H₆ has
- Q1 What would be the electron dot structure of carbon dioxide which…
- Q2 Butanone is a four-carbon compound with the functional group
- Q2 What would be the electron dot structure of a molecule of sulphur w…
- Q3 While cooking, if the bottom of the vessel is getting blackened o…
- Q4 Explain the nature of the covalent bond using the bond formation…
- Q5 Draw the electron dot structures for (a) ethanoic acid. (b) H₂S. (…
- Q6 What is an homologous series? Explain with an example.
- Q7 How can ethanol and ethanoic acid be differentiated on the basis…
- Q8 Why does micelle formation take place when soap is added to water…
- Q9 Why are carbon and its compounds used as fuels for most applic…
- Q10 Explain the formation of scum when hard water is treated with s…
All 442 questions on Carbon and its Compounds → Browse all Science chapters →