The Solubility of Potassium Nitrate
Aim
To investigate how the solubility of Potassium Nitrate is affected by
Temperature.
Background Knowledge
Potassium Nitrate (KNO3) is an ionic compound. The strong ionic bonds
hold the compound in an ionic lattice which gives KNO3 its crystalline
structure. These ionic bonds also have other properties which will
affect my investigation, I must be aware of these properties for
greater accuracy in my method. The ionic bonds give KNO3 high melting
and boiling temperatures. In the case of KNO3, ionic bonds are
present, which are strong and hard to break under room temperature; I
believe that this may have an impact on the solubility of KNO3 at low
temperatures, where there is very little energy present to break these
bonds.
Particles move faster and collide with a greater energy output. A
greater proportion of these particles now have enough energy to react.
Therefore there is a greater chance of a collision between KNO3 and
water molecules resulting in a successful reaction.
Hypothesis
My hypothesis is that the temperature of the water affects the
solubility of Potassium Nitrate. As I have already addressed this, as
you increase the temperature, you also increase the kinetic energy of
each particle; thus increasing the chance of a successful reaction.
This means more potassium nitrate will be broken down and dissolved in
the water as the temperature increases. I believe that the solubility
of the KNO3 will increase at a proportional rate to the increase in
the temperature of the water.
[IMAGE]When the KNO3 dissolves, it can be classed as a chemical
reaction. It follows therefore that in order for the KNO3 to dissolve,
an activation energy barrier must be overcome. Activation energy is
the energy required to kick-start a chemical reaction. If the
activation energy barrier is not reached (i.e. if the particles do not
have enough energy on collision to react) then the reaction will not
proceed and the KNO3 cannot dissolve in the water.
In order for KNO3 to be dissolved, it must come into contact with
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.
The researcher conducting this experiment is trying to find out which salt- Epsom, table salt, and sea salt- will increase the boiling point of water the most. Sodium chloride is believed to increase the boiling point of water because when salt is suspended into the water, the sodium and chlorine ions leave the “salt crystals” and mix with the water molecules. (“Why does salt… raise boiling point of water?”, 2009).
Potassium is freely filtered in the glomerulus. Two thirds of the potassium is reabsorbed along the proximal tubule. The potassium concentration in the proximal tubule is roughly equal to that of plasma. In the descending limb of Henle a small amount of potassium is secreted into the luminal fluid and is reabsorbed by the ascending limb of Henle. The concentration of potassium is the distal convoluted tubule is now lower than the concentration in the plasma. The connecting tubule and cortical connecting tubule actively secrete potassium into the lumen. Potassium is then reabsorbed in the medullary segment while the excess is excreted in urine.[5&6]
A precipitation reaction can occur when two ionic compounds react and produce an insoluble solid. A precipitate is the result of this reaction. This experiment demonstrates how different compounds, react with each other; specifically relating to the solubility of the compounds involved. The independent variable, will be the changing of the various chemical solutions that were mixed in order to produce different results. Conversely the dependent variable will be the result of the independent variable, these include the precipitates formed, and the changes that can be observed after the experiment has been conducted. The controlled variable will be the measurement of ten droplets per test tube.
Such as Potassium Carbonate ( CK2O3 ) has an average mass of 138.206 Da. It’s appearance is a powder that is white in color. It is stable and incompatible with moisture and acids.Potassium carbonate is used in pharmaceutical labs to help aid in the drying process. Potassium Nitrate ( KNO3) has an average mass of 101.103 Da with a colorless crystal appearance or in white powder form. It is soluble in water, glycerol, and liquid NH3. It is stable and a strong oxidizer that has a melting point at 334 degrees celsius.Potassium nitrate is found in fertilizers, gunpowder, and in fireworks. Potassium hydrogen carbonate ( KHCO3 ) has an average mass of 100.115 Da and is stable. It also has a white powder or crystal appearance with a melting point at 100 degrees
Potassium is an element on the periodic table that is symbolized by the letter K. The atomic number of this element is 19. At room temperature this element is a solid. Potassium can be found in two forms: either pure or compounds. Pure potassium is described as a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive in water However, Potassium forms many compounds such as Potassium chloride, which is the most common potassium compound (Gagnon, 1). This form of Potassium is especially used in fertilizers as a salt substitute. Another potassium compound is Potassium hydroxide, which is used to make soap, detergents and drain cleaners. Potassium carbonate is used to make some types of glass and soaps. This is also obtained as a byproduct of ammonia. Lastly, Potassium superoxide can create oxygen from water vapor and carbon dioxide. An example of this reaction is “2KO2 + H2O + 2CO2 => 2KHCO3 + O2” (Gagnon, 1). Gagnon also says, “it is used in respiratory equipment and is produced by burning potassium metal in dry air. Potassium nitrate (KNO3), also known as saltpeter or nitre, is used in fertilizers, match heads and pyrotechnics” (Gagnon, 1). Sir Humphrey Davy discovered this element in England in 1807 (Helmenstine, 1). Steve Gagnon, maintainer of the Jefferson Lab website page says, “Sir Humphry Davy first isolated metallic potassium in 1807 through the electrolysis of molten caustic potash (KOH)” (Gagnon, 1). Gagnon also writes, “a few months after discovering potassium, Davy used the same method to isolate sodium. Potassium can be obtained from the minerals sylvite (KCl), carnallite (KCl·MgCl2·6H2O), langbeinite (K2Mg2(SO4)3) and polyhalite (K2Ca2Mg(SO4)4·2H2O). These minerals are often found in ancient...
It is important however to note that the NH4 and K ions are still in
The % composition by mass of oxygen in Potassium Chlorate was found to be 43.4%.
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.
5. Add Hcl, as soon as it mixes with the ( ), start the stopwatch
Electrical conductivity refers to a substances ability to carry moving electrons (conduct electricity). In order to do so, there must be a supply of delocalised electrons. While in a solid state, ionic substances can not conduct electricity as there are no delocalised electrons or free/mobile ions to act as charge carriers. In an aqueous ionic solution, the H2O molecules break apart the crystal lattice structure of the ionic substance into individual ions, surrounding each ion in a jacket of hydration. Below is the equation that describes the dissociation of NaCl when in H2O solvent.
Looking at the table of results above and the graph, it is shown that the higher the temperature got, the shorter the reaction time. The obtained results have been plotted on a line graph of the temperature of hydrochloric acid (y-axis) against reaction time (x-axis). This line graph in fig.2 also clearly shows that as the temperature increases, so does the speed of the reaction, shown by a reduction in the time taken. This corroborates the collision theory, where as the temperature of particles increase, the particles gain more kinetic energy and react with each other upon collision. This is shown as to happen in the hydrochloric acid, where the hydrochloric acid particles collide more with the particles of the magnesium ribbon as the temperature was increased. The above graph shows a gradual sloping curve, which gets steeper at higher temperatures. This shows that the reaction will reach a peak rate of activity as the gaps between the temperature and reaction times continue to decrease. The experiment fulfills the aim and clearly shows that as the temperature of a reaction is increased so does it’s rate of reaction, proving the hypothesis to be correct.
This experiment consists of titrating the ferrous ion with permanganate ion to study the oxidation-reduction reaction. The ions react in acidic solution to give ferric ion and a reduced ionic form of manganese. All the reactants and products except permanganate ion are weakly colored, whereas permanganate is a very intensely colored ion. Then a solution of permanganate is removed as long as there is a ferrous ion present to react with it. But as soon as the entire ferrous ion has been oxidized, the next small portion of added permanganate colors the solution. The first appearance of a permanent pink color indicates the endpoint of the experiment. From the titration it will be able to calculate the percentage of iron in the sample from the data.
6. I then rinsed out the beaker and glass rod into the flask to make
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).