NEB Science 10 — SEE Practical Lab

Every SEE candidate sits a science practical examination, and every one of those practicals is a procedure you can rehearse here before you touch the real apparatus. Measure the focal length of a concave mirror and follow the rays; build a circuit, take voltage-current readings and get the resistance from the slope of your own graph; test a set of household substances with litmus, phenolphthalein and methyl orange; and run the iodine, Benedict's and Biuret tests that tell starch, sugar and protein apart. Readouts, observations and conclusions follow the format the marker expects in your practical answer sheet.

You will learn: doneMeasuring focal length and drawing ray diagrams for a concave mirror doneTaking voltage and current readings and plotting a V-I graph doneFinding the equivalent resistance of series and parallel combinations doneUsing indicators to classify a solution as acidic, basic or neutral doneRunning and interpreting iodine, Benedict's and Biuret food tests doneRecording observation, inference and conclusion in the practical format

play_arrow Start course play_lesson4 lessons schedule~56 min total

Lessons

1 flare Focal Length of a Concave Mirror Move an object along the principal axis of a concave mirror and watch the image change — real, inverted and diminished far away, then magnified near the focus. Switch to the distant-object method to measure f the way the school lab does. Virtual lab 14 min done 2 electrical_services Ohm's Law and Resistor Combinations Wire a cell, an ammeter and one or two resistors in series or parallel. Raise the voltage, record the current, and read the resistance off the slope of the V-I graph you built yourself. Virtual lab 16 min done 3 water_drop Acids, Bases and Indicators Test lemon juice, curd, lime water, soap, baking soda and a salt solution with litmus paper, phenolphthalein, methyl orange and universal indicator — and watch the colour change decide the answer. Virtual lab 13 min done 4 restaurant Food Tests: Starch, Sugar and Protein Run the three food tests on rice, potato, bread, banana, milk, egg white, soybean and groundnut, and work out what each food contains from the colour change. Virtual lab 13 min done