Rp 01- Making A Standard Solution And Carrying Out An Acid Base Titration

Question 1

What’s a standard solution

Answer 1

A solution of known concentration

Question 2

How do you make a standard solution?

Answer 2

• measure the mass of solid required using a balance.
• transfer this to a volumetric flask, rinse remaining weighing bottle content into the flask so no solid lost.
• add volume of distilled water to dissolve the solid
• swirl to mix
• add more distilled water up to the line on the volumetric flask.
• invert multiple times to mix

Question 3

What is weighing by difference?

Answer 3

Method to weigh materials accurately
Mass of substance = mass of weighing boat and substance - mass of dish after substance is transferred

Question 4

What equipment is used to carry out a titration

Answer 4

• pipettes and pipette filler used to accurately out the volume of a reactant before transferring to a conical flask
• burette used to add small volumes of one reactant to the other

Question 5

How do you carry out a titration ?

Answer 5

• once the pipette has been used to place one reactant into the conical flask, fill the burette with the other reactant. Record initial volume
• add few drops of indicator to conical flask
• open the burette tap and allow the reactant to flow into the conical flask, swirl to mix contents
• close the burette tap once the expected colour change occurs. Use a white tile so the colour change is easy to see.
• record final burette volume
• repeat till get concordat results, then calc. Mean titre

Question 6

Why are acid-base indicators used?

Answer 6

To detect when a reaction reaches completion, usually by presence of colour change

Question 7

What are concordat results?

Answer 7

Titres that are within O.1cm3 of each other