Insert a lighted splint into a test tube of the gas. If the lighted splint is extinguished with a ‘pop’ sound, it shows the presence of hydrogen gas.
Month: November 2023
Describe the test for Cu2+ ions using aqueous sodium hydroxide.
Add a few drops of aqueous sodium hydroxide into a sample of the solution, followed by adding aqueous sodium hydroxide in excess. If a blue precipitate forms which is insoluble in excess of aqueous sodium hydroxide, it shows the presence of Cu2+ ions.
Define electromagnetic induction.
Electromagnetic Induction is a process in which an electromotive force (e.m.f.) is induced in any conductor whenever there is a change in the magnetic flux linkages through the conductor.
Define induced magnetism.
Induced magnetism occurs when a magnetic material is placed near to, or touching, any pole of a permanent magnet, thereby becoming an induced magnet itself.
Once removed from permanent magnet, induced magnet will lose its magnetism.
Define light-dependent resistor.
A light-dependent resistor (LDR) is a type of transducer which responds to a change in light intensity. Its resistance decreases when light intensity increases, and vice versa.
Define transducer.
A transducer is an electrical device which can convert energy from one form to another.
Define Ohm’s Law.
Ohm’s Law states that the current through a metallic conductor is directly proportional to the potential difference across it, if the temperature is constant.
Define resistance.
Resistance is the ratio of the potential difference applied to the current flowing through.
Define potential difference.
Potential difference is the work done to drive a unit charge across two points in a circuit.
Define electromotive force.
Electromotive force is the work done by a source in driving a unit charge around a complete circuit.