Download App

Chemistry in Everyday Life — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryChemistry in Everyday Life3 Marks
Question
Explain the following terms with one example in each case:
  1. Food preservatives.
  2. Enzymes.
  3. Detergents.
✓

Answer

  1. Food preservatives: Are the compounds which prevent spoilage of food due to microbial growth. eg: Sodium benzoate, vinegar.
  2. Enzymes are the biological catalysts which increase the rate of metabolism. eg: Invertase, Zymase,
  3. Detergents are sodium salts of long chain alkyl sulphonates or benzene sulphonates. eg: Sodium Lauryl sulphate.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "3 Marks Question" from Chemistry in Everyday Life→Chemistry in Everyday Life — all question types→Chemistry STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

In a reaction between A and B, the initial rate of reaction $(r_0)$ was measured for different initial concentrations of A and B as given below:
$A/mol L^{-1}$ $0.20$ $0.20$ $0.40$
$B/mol L^{-1}$ $0.30$ $0.10$ $0.05$
$r_0/mol L^{-1} s^{-1}$ $5.07 \times 10^{-5}$ $5.07 \times 10^{-5}$ $1.43 \times 10^{-4}$
What is the order of the reaction with respect to $A$ and $B$?
→
An unknown aldehyde ‘A’ on reacting with alkali gives a β-hydroxy aldehyde, which loses water to form an unsaturated aldehyde, 2-butenal. Another aldehyde ‘B’ undergoes disproportionation reaction in the presence of conc. alkali to form products C and D. C is an arylalcohol with the formula, $C_7H_8O$.
  1. Identify A and B.
  2. Write the sequence of reactions involved.
  3. Name the product, when ‘B’ reacts with zinc amalgam and hydrochloric acid.
→
Write the mechanism of acid dehydration of ethanol to yield ethane.
→
  1. What is the role of t-butyl peroxide in the polymerization of ethene?
  2. Identify the monomers in the following polymer:
$– [NH – (CH_2)_6 – NH – CO – (CH_2)_4 – CO– ]_n$
  1. Arrange the following polymers in the increasing order of their intermolecular forces:
Polystyrene, Terylene, Buna-$S.$
→
Aqueous copper sulphate solution and aqueous silver nitrate solution are electrolysed by $1$ ampere current for $10$ minutes in separate electrolytic cells. Will the mass of copper and silver deposited on the cathode be same or different? Explain your answer.
→
An element crystallizes in a f.c.c. lattice with cell edge of $400$ pm. Calculate the density if $200$ g of this element contain $2.5 \times 10^{24}$ atoms.
→
In a pseudo first order hydrolysis of ester in water, the following results were obtained:
t/s $0$ $30$ $60$ $90$
[Ester]/mol $L^{-1}$ $0.55$ $0.31$ $0.17$ $0.085$
  1. Calculate the average rate of reaction between the time interval $30 $to $60 $seconds.
  2. Calculate the pseudo first order rate constant for the hydrolysis of ester.
→
What are enantiomers? Draw the structures of the possible enantiomers of 3-methylpent-1-ene.
→
Discuss applications of $d$ and $f-$Block element.
→
A crystalline solid has a cubic structure in which tungsten $(W)$ atoms are located at cube corners of the unit cell, oxygen atoms at the cube edges and sodium atom at the centre. What is the molecular formula of the compound?
→