The Determination of the Solubility of Calcium Hydroxide
I have to plan an experiment to find the solubility of calcium
hydroxide, Ca(OH)2, in water. I have to make up a solution of calcium
hydroxide and carry out a titration using hydrochloric acid solution
of the chosen concentration.
The equipment need is as below:
· Solid calcium hydroxide
· Methyl orange indicator
· Volumetric flask (250cm3)
· Clamp and boss
· Clamp stand
· Burette (50cm3)
· Conical flask
· Pipette (25cm3)
· Pipette filler
· Distilled water
· White spotting tile
· Hydrochloric acid of chosen concentration
· Beaker x2
· Rubber bung
· Funnel x2
· Electronic scale
‘The maximum mass of calcium hydroxide needed to produce 1dm3 of
saturated solution at room temperature is 1.5g.’
I only want 250cm3 as I am using a 250cm3 volumetric flask. Therefore:
1dm3 / 4 = 250cm3
1.5g / 4 = 0.375g
The number of moles in volumetric flask:
0.375 / 74 = 0.005 moles
I need an excess of 0.5g to make sure that all the calcium hydroxide
has been fully dissolved:
0.375g + 0.5g = 0.875g
I have to now work out the concentration of hydrochloric acid I will
be using. The molar mass of calcium hydroxide is:
C = 40 O = 16 (x2) H = 1 (x2)
R.A.M = 74
The concentration of calcium hydroxide at the beginning will be:
1.5 / 74 = 0.02
So, the concentration is 0.02 mol/dm3
In the experiment I will be using 25cm3 of the solution from the
volumetric flask, so the mass of the calcium hydroxide in one
titration will be:
0.375 / 10 = 0.0375g
Therefore the number of moles of calcium hydroxide:
0.0375 / 74 = 0.0005 moles
Ca(OH)2(aq) + 2HCl à CaCl2(aq) + 2H20(l)
The purpose for this lab was to use aluminum from a soda can to form a chemical compound known as hydrated potassium aluminum sulfate. In the lab aluminum waste were dissolved in KOH or potassium sulfide to form a complex alum. The solution was then filtered through gravity filtration to remove any solid material. 25 mLs of sulfuric acid was then added while gently boiling the solution resulting in crystals forming after cooling in an ice bath. The product was then collected and filter through vacuum filtration. Lastly, crystals were collected and weighed on a scale.
We were then to make a base solution of 0.7 M NaOH. In order to standardize
Apparatus: * 1 measuring cylinder * 1 test tube * 1 stop clock * A large gelatine cube containing indicator and NaOH * Hydrochloric acid ranging from 1-3 molars * A scalpel Diagram: Method: * Take the large gelatine cube and cut into 15 equal pieces * Place on piece of the cube into the test tube * Measure out 10mls of HCl in the measuring cylinder * Pour the HCl into the test tube with the gelatine cube and start the clock * Time how long it takes for the pink colour inside the gelatine cube to completely disappear * You will also notice that the cube dissolves slightly * Record your results and repeat this same process 3 times for each molar of acid: § 1 molar § 1.5 molar § 2 molar
3. Add on of the following volumes of distilled water to the test tube, as assigned by your teacher: 10.0mL, 15.0mL, 20.0mL, 25.0mL, 30.0mL. (If you use a graduated cylinder, remember to read the volume from the bottom of the water meniscus. You can make more a more accurate volume measurement using either a pipette or a burette.)
Solubility is defined as the maximum amount of a substance that will dissolve in a given amount of another substance at constant temperature and pressure. Solubility is typically expressed in terms of maximum volume or mass of the solute that dissolve in a given volume or mass of a solvent. Traditionally the equilibrium solubility at a given pH and temperature is determined by the shake flask method. According to this method the compound is added in surplus to a certain medium and shaken at a predetermined time. The saturation is confirmed by observation of the presence of un-dissolved material. Saturation can also be reached if the solvent and excess solute is heated and then allowed to cool to the given temperature. After filtration of the
= 3 ´ E(C-H) + 1 ´ E(C-O) + 1 ´ E(O-H) + 1.5 ´ E(O=O)
-443.08 x (100.1 / 2.51) = -17670.2 J.mol. 1. H = -17.67 kJ.mol. 1.
Once the mixture had been completely dissolved, the solution was transferred to a separatory funnel. The solution was then extracted twice using 5.0 mL of 1 M
Determining the Concentration Of Limewater Solution Aim: The aim of this experiment is it to find out the concentration of Limewater by performing a titration with hydrochloric acid which has concentration exactly 2.00M.. What is required for me is that I have to design my own experiment and chose the right and appropriate apparatus and equipment. I will be provided with 250cm3 of limewater, which has been made to which contains approximately 1g/dm3 of calcium Hydroxide. This hypothesis from www.studentcentral.co.uk We were also give Hydrochloric acid (HCl) with a concentration of 2.00 mol/dm3 normal laboratory apparatus was also given and so was an indicator.
Water is the most important molecule that exists on the Earth. Without water living beings would not be able to live. Water is used for an immeasurable number of things. There are many properties of water, which makes this molecule so unique. One which people overlook is hardness. Hardness is defined in the Chemistry: The Central Science by Prentice Hall's as being "water that contains a relatively high concentration of Ca2+, Mg2+, and other divalent cations." Water containing these ions is not a health hazard; however, it is a problem for industries and households. Therefore, the hardness of water is vital to understand in order to prevent the problems it could cause.
The amount of hydrochloric acid. 3. The concentration of the hydrochloric acid. 4. The surface area of the calcium carbonate.
Weigh accurately about 0.3 g and dissolve in 40 ml of me-thanol. Titrate with 0.1 M so-dium hydroxide.
of Copper Sulphate. To do this I plan to work out the amount of water
second test tube also add 6 mL of 0.1M HCl. Make a solution of 0.165
The purpose of this experiment is to use our knowledge from previous experiments to determine the exact concentration of a 0.1M sodium hydroxide solution by titration (Lab Guide pg.141).