Unit 1 - The Mole T3

Question 1

What is mole

Answer 1

Mole is a number used to measure out equal amounts of a substance.

Question 2

Gram formula mass

Answer 2

Mass of one mole for a substance

Question 3

Standard solution

Answer 3

Solution of an accurately known concentration.

Question 4

Preparing a standard solution.

Answer 4

Equipment needed - volumetric flask, wash bottle, beaker, 3dp balance, stirring rod, spatula, deionised water and dropper pipette.
􏰀 Take a clean, dry beaker and place it on the balance. Tare the balance (set it
to zero). Carefully weigh out the required mass of solute.
􏰀 Add deionised water from a wash bottle to dissolve it and stir with a glass rod
until all of the solid is dissolved.
􏰀 Transfer the solution to a volumetric flask. Use deionised water from the wash bottle to rinse out the beaker and rinse the glass rod. Do this at least twice.
􏰀 Add water from the wash bottle to just below the line on the flask. Add the last few drops with a dropper pipette to make sure that the bottom of the meniscus is on the line.
􏰀 Put the lid on the flask and invert it several times to ensure thorough mixing.
When answering question draw diagram and work out mass needed.