Weighing balance, Watch glass, Weight box, 250ml beaker, Glass rod, 250cm3 measuring flask / Volumetric flask, Wash bottle, Weighing tube, Oxalic acid, Funnel, Funnel stand, Distilled water
- Mass (m) of the solute expressed in grams = MVMm/1000
- M – Molarity of the solution
- V- Volume of the solution in cm3
- Mm – Molar mass of the solute
- Hydrated oxalic acid = C2H2O4.2H2O
- Molecular mass of Oxalic Acid = 126.
- 12.6 g of oxalic acid per litre of the solution should be dissolved to prepare M/10 oxalic acid solution.
- Mass = 0.1 (mol)* 250(cm3) *126 (g mol-1)/ 1000 (cm3)
- Mass = 3.1500g
Real Lab Procedure
- Take a dry watch glass and take the empty weight of the watch glass
- Weigh the exact amount of clean and dried watch glass.
- Weigh correctly on the watch glass 3.1500 g of oxalic acid and record this weight in the notebook.
Note: Always note weight up to the fourth decimal place and clean the balance before and after weighing the chemical.
- Using a funnel, transfer oxalic acid softly and carefully from the watch glass into a clean and dry measuring flask.
- Wash the watch glass with distilled water to move the particles that stick to it into the foam with the assistance of a wash bottle.
Note: For this purpose, the volume of distilled water should not exceed 50 ml.
- Wash funnels several times with distilled water to move the sticking particles into the measuring flask using a wash bottle. Add water in tiny quantities while washing the funnel. The distilled water quantity used for this purpose should not exceed 50 mL.
- Using a wash bottle, wash the funnel carefully with distilled water to pass the solution attached to the funnel into the measuring flask
- Turn the flask of measurement until the oxalic acid dissolves.
- Using a wash bottle, thoroughly add enough distilled water to the measuring flask just below the etched mark on it.
- Add the last few mL of distilled water drop into the measuring flask until the reduced meniscus level just touches the mark.
- Put the stopper on the mouth of the flask and shake softly to make the entire solution uniform. Calculate it as a solution of oxalic acid M/10.
- Drag and drop watch glass onto the weighing machine to measure weight of the watch glass
- Click on the bottle cap to open it
- Drag and drop the spatula towards the bottle to take (3.1500)gm of oxalic acid
- Drag and drop the spatula towards the watch glass to transfer oxalic acid to watch glass.
- Drag and drop the watch glass towards the funnel placed at the top of the measuring flask
- Drag and drop the wash bottle to the top of the funnel to wash and pour any remains present inside the funnel
- Drag the funnel outside the measuring flask and place it inside a stand.
- Drag and drop the measuring flask on the canvas to shake it
- Drag and drop the dropper to the beaker collect some water from beaker
- Drag and drop the dropper containing distilled water to the top of the measuring flask to pour the water inside it.
- Drag and drop the stopper to close the measuring flask when the required quantity is there
- Drag and drop the measuring flask on the canvas to shake it.
- Click the reset button to redo the program
|Weight of the watch glass
|Weight of the watch glass + Oxalic acid
||W1 + 3.15g
|Weight of Oxalic acid
||3.150g (Weight of watch glass – Weight of oxalic acid)
|Volume of distilled water
250cm3 of decimolar or (M/10) solution of oxalic acid is prepared.
- Handle chemicals carefully.
- Keep the weighing balance clean and neat.
- Handle glass apparatus carefully.
- Ensure the water level of the chemical balance is in the right position.
- Use lab coats, gloves and googles while handling the chemicals.