This is my Unit 2 assignment, it contains part A of assignment unit 2 Practical Scientific Procedures and Techniques of BTEC applied science. i gained a DISTINCTION for this assignment, the assignment includes: Preparing a standard solution of sodium carbonate solution, a titration experiment, and...
Preparing 250cm3 of 0.5 mol.dm-3 Sodium Carbonate solution
Standard solution: a solution containing a precisely known concentration of an element or
substance.
Method:
o Calculate the mass of sodium carbonate solid needed to produce 250 cm 3 of a 0.500 mol dm-3
solution. To do this you need to:
Calculate the Mr of Na2CO3 : (23 x 2) + 12 + (16 x 3) = 106
You know the wanted concentration is 0.5 mol/dm 3 so to find the mass needed use the
mass
equation Moles= 0.5 x 106 = 56g
mr
56/4 = 13.25
o Put a clean, dry weighing boat on a balance and reset to zero.
o Using a spatula, place into the boat 13.25g of sodium carbonate.
o Pour the contents of the weighing boat into a beaker ensuring that all of the powder is
transferred.
o Add approximately 100 cm3 of distilled water to the beaker containing the solid and use a glass
rod and stir the contents of the beaker until all of the sodium carbonate dissolves.
o Using a funnel, pour the contents of the beaker into a 250 cm3 volumetric flask then using the
wash bottle rinse the beaker and funnel into the same volumetric flask. Rinse the glass rod into
these washings.
o Make the volumetric flask up to the graduated mark by carefully adding distilled water from the
wash bottle. You will need to be careful so that you do not over-shoot the mark.
o Stopper the volumetric flask and shake it thoroughly to mix the contents of the flask.
Risk assessment :
Hazard Risk Action
glassware It can break and cut E.g. take extreme care when
your hand handling the beakers and volumetric
flasks
Sodium carbonate it can get into eyes E.g. wear goggles to protect eyes
Tripping you can fall over E.g. tuck the chairs under the tables
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller assignmentseller123. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £10.49. You're not tied to anything after your purchase.