of the coil using metre scale Observations: (i) To find the resistance: S. No Ammeter reading-I (Ampere) Voltmeter reading-V (Volt) Resistance = V/I (Ohm) MEAN (ii) To find the diameter of the wire using screw gauge: S. No Pitch Scale reading-PSR (mm) Head scale coincidence-HSC Head scale reading- HSR=HSC×LC (mm) Total reading = PSR + HSR (mm) Mean Diameter Calculations: Radius of the wire, r = diameter/ = m Area of cross section of the wire, A = π r = m Length of the wire L = m. Resistivity of the material of the wire = = Ω m Result: The resistivity of the material of the wire = Ω m Practicals .
IDENTIFY THE DISSOLUTION OF THE GIVEN SALT WHETHER IT IS EXOTHERMIC OR ENDOTHERMIC. Aim: To test the dissolution of given salt is exothermic or endothermic Principle: If the reaction or process liberates the heat, then it is called exothermic. If the reaction or process absorbs the heat, then it is called endothermic Apparatus required: Two beakers, Thermometer, stirrer ,weighed amount of two samples. Procedure: Take 50ml of water in two beakers and label them as A and B.
Note the temperature of the water from beaker A and B. Then, add 5g of sample A into the beaker A and stir well until it dissolve completely. Record final temperature of the solution. Now, repeat the same for the sample B.
Record the observation. Observation: S. No Sample Temperature before addition of sample ( o C) Temperature after addition of sample ( o C) Inference (temperature increases or decreases) A B Result: From the inferences made The dissolution of sample A is (Exothermic or endothermic) The dissolution of sample B is (Exothermic or endothermic) Note: Sodium hydroxide, ammonium nitrate, glucose, calcium oxide etc. may be given as the sample.
CHEMISTRY . TESTING THE WATER OF HYDRATION OF SALT Aim: To check whether the given sample of salt possesses 'Water of