Chemistry Project Report Project Report on Acid & Bases of Tensile Strength of Fibres

Chemistry Project Report Project Report on Acid & Bases of Tensile Strength of Fibres

Chemistry Project Report on “Acid & Bases on Tensile Strength of Strength of Fibres”


I, ____________ scholar of ___________________ is doing undertaking report on “Acid & Bases on Tensile Strength of Strength of Fibres” being submitted to ___________________is an authentic piece of work done by means of me and has no longer been posted or submitted elsewhere for any other diploma in full or in part.


Acid & Bases on Tensile Strength of Strength of Fibres


“Project Report Effects of Acids & Bases at the Tensile Strength of Fibres”

The aim and goal of this assignment is to

(i) Compare the tensile power of given samples of nylon and cotton fibres.

(ii) To check out the Effect of Acids and Alkalies on the tensile electricity of those fibres.

Depending upon the resources, the numerous varieties of fibres can be categorised into the following 3 most important classes :
(i) Animal fibres e.G. Wool & Silk.
(ii) Vegetable Fibres e.G. Cotton & Linen.
(iii) Synthetic Fibres e.G. Nylon & Polyester.

Besides their chemical composition and homes, maximum vital belongings of these fibres is their tensile energy. Tensile energy mean the extent to which a fibre may be stretched with out breaking and it is measured in terms of minimal weight required to interrupt the fibre. To decide the tensile strength of any fibre, it is tied to a hook at one stop and weighted are slowly introduced to the other give up until the fibre smash.
Since peptide bonds are extra without problems hydrolyzed by bases than acids consequently wool and silk are affected by foundation no longer by means of acids. It is because of this motive that wool and silk threads breakup into fragments and ultimately dissolve in alkalines.

In other words alkalines decreases the tensile power of animal fibres (wool & silk). Vegetable fibres (cotton & linen), however, encompass lengthy polysaccharide chains wherein the numerous glucose devices are joined by ethers linkage. Since ethers are hydrolised by using acids and now not by way of bases consequently, vegetable fibres are suffering from acids however no longer through bases. In other phrases acids decreases the tensile strength of vegetable fibres. In evaluation, synthetics fibres together with nylon & polyester practically stays unaffected by each acids and bases.

Experiment-1 [Acid and Bases]

Requirements :

(a) Apparatus : Hook, Weight hanger and weights.

(b) Materials : Cotton, Silk and Nylon fibres.

Chemistry Experiment Acid and Bases Procedure

(i) Cut out identical lengths of a cotton fibre, nylon fibre and silk fibre from the given sample of almost same dia.

(ii) Tie one stop of cotton fibre to a hook which has been constant in a vertical plane. Tie a weight hanger to the other end. The thread get directly.

(iii) Put a weight to the hanger and examine the thread stretch. Then, increase the weights progressively on the hanger till the breaking point reaches and notice the minimum weight wished for breaking the cotton fibre.

(iv) Repeat the above test by way of tying nylon and silk fibres to the hook one after the other.

Sr.No. Type of Fibre Minimum Weight

1. Cotton 75 g.

2. Nylon 375 g.

3. Silk one hundred fifty g.


(i) Thread ought to be of equal diameters.

(ii) Always take the same duration of the threads.

(iii) Add the weights in small amounts very slowly.

Experiment – 2

Requirements :

(a) Apparatus : Hook, Weight Hanger and Weights.

(b) Materials and Chemicals : Wool, Cotton and Nylon Fibres, dilute answer of hydrochloric acid and sodium hydroxide.


(i) Cut out identical lengths of wool, cotton and nylon threads from given pattern of almost equal diameter.

(ii) Determine the tensile power of every fibre as defined in test-1.

(iii) Soak the woolen thread in a dilute solution of sodium hydroxide for 5 minutes. Take it out from hydroxide solution and wash it very well with water after which dry either by retaining it inside the sun or in an over maintained at a temperature of about 400C. Determine its tensile power again as explained in Experiment-1.

(iv) Now take another piece of woolen thread of the identical size and diameter and soak it in a dilute solution of hydrochloric acid for 5 minutes. Take it out, wash very well with water, dry and decide the tensile strength again.

(v) Repeat the above system for the samples of cotton and nylon fibre.

S.No. Type of Wt. Required Wt. Required Wt.Required

Fibre to interrupt the to interrupt the to interrupt the

untreated fibre fibre after fibre after

soaking in soaking in

dilute alkali dilute acid

1. Wool 750 g. 700 g. 750 g.

2. Cotton 75 g. 75 g. 50 g.

Three. Nylon 375 g. 375 g. 375 g.


(i) The tensile strength of woolen fibre decreases on soaking in alkalies but nearly remains unaffected on soaking in acids.

(ii) The tensile strength of cotton fibre decreases on soaking in acids however remains almost unaffected on soaking in alkalies.

(iii) The tensile electricity of nylon fibres remain practically unaffected on soaking either in acids or in alkalies.


(i) Thread need to be of same diameters.

(ii) Always take the equal length of the threads.

(iii) Add the weights in small amounts very slowly.

Updated: April 4, 2017 — 9:29 am

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