science teacher's guide - DepEd Naga City

Teacher's GuideModule 3: Elements & CompoundsConstruction of an Improvised Electrolysis Apparatus3. Divide the plastic bottle into three portions. Mark “cutting lines”around the bottle. Refer to the figure on the right.Distance between cutting-line marks: Bottom portion (3): about 5 cm from thebottom part of the bottle.1Middle portion (2): about 6 cmfrom the marked line of thebottom portion (3)236 cm5 cmHeat the stripping knife in an alcohol lamp. Use the hot strippingknife to cut around these line marks.4. Use the middle portion of the bottle tomake a stand for the sample container.Make two small squares measuring about 2cm x 2 cm at opposite sides of the base.These will serve as passageway for theconnecting wires.2cm x x 22cm5. Use the bottom portion of the bottle as the samplecontainer. Measure the distance betweenthe centers of the “electrolysis syringes”.Mark this length with a line on thebottom of the cup. Then using a hot GIwire (2 mm in diameter) bore a small holeat each end of the line. The stainless screwswill pass through these holes.Grade 7 Science: MatterDiversity of Materials in the Environment 32