SOLUTION
Purpose
Knowing how to create a solution
II. Basic theory
Solution is a homogenous mixture. A mixture is said homogeneous if there is no field of inter-component boundaries so that no longer distinguishable despite using ultra microscope. In addition, the homogenous mixture has the same composition in each part.
Solution consisting of solvent (solvent) and solutes (solutes). Typically, the most amount component which is considered as a solvent, but if the liquid solution, then the fluid is considered as a solvent. For example syrup, which is a mixture that contains more sugar than water, is considered as a solution in the sugar.
Solution concentration is the amount of solute contained in a certain amount of solution. Molarity concentration expressed as the number of moles of solute in 1 L solution. Dilution is the process of adding solvent to a solution, which will reduce the concentration (molarity) solution without changing the total number of moles of solute contained in the solution.
In chemistry, a solution is a homogeneous mixture consisting of two or more substances. A smaller number of substances in solution is called (substances) dissolved or solutes, whereas substances that amount more than other substances in solution is solvent or solvents. The composition of the solute and solvent in solution is expressed in concentration of the solution, while the mixing process of the solute and solvent form a solution is called dissolution or solvation. Example of a common solution is the solids dissolved in liquids, such as salt or sugar dissolved in water. Gas also can be dissolved in a liquid, such as carbon dioxide or oxygen in the water. In addition, the fluid can also be dissolved in another liquid, while gas dissolved in another gas. There is also a solid solution, such as alloy (mixed metal) and certain minerals. Concentration Solution concentration expressed in quantitative composition of the solute and solvent in the solution. Concentrations are usually expressed in comparison with the amount of the total amount of solute substance in solution, or in comparison with the total amount of solute solvent. Examples of some unit of concentration is a molar, molal, and parts per million (parts per million, ppm). Meanwhile, qualitatively, the composition can be expressed as a dilute solution (low concentration) or concentrated (high concentration).
Dissolution
Sodium ion solvated by water molecules. Molecular components interact directly in a state of solution mixed. In the process of dissolution, the pull of pure component between particle fragmented and replaced with the attraction between the solvent with the solute. Especially if the solvent and solute are both polar, will form a solvent structure around the solute; this allows the interaction between the solute and solvent remained stable.
When the solute component is added continuously into the solvent, at a point component that is added will not be late again. For example, if the substance fused a solid and a liquid solvent, at some point can not be dissolved solids again and formed sediment. The amount of solute in the solution is maximal, and the solution was called as a saturated solution. The point of the achievement of being saturated solution is strongly influenced by various environmental factors, such as temperature, pressure, and contamination. In general, the solubility of a substance (ie the amount of a substance that can be dissolved in certain solvents) is proportional to the temperature. This is especially true in solids, although there are exceptions. Liquid solubility in other liquids are generally less sensitive to temperature than the solubility of solids or gases in liquids. Gas solubility in water is generally inversely proportional to temperature.
Ideal solution
When the intermolecular interaction of components of the solution together with intermolecular interaction components in pure state, it becomes an idealization that is called an ideal solution. Ideal solution obey the Raoult law, namely that the vapor pressure of solvent (liquid) with a straight right versus mole fraction of solvent in the solution. Solution is really ideal does not exist in nature, but some solutions meet the Raoult law to certain limits. Examples which may be considered ideal solution is a mixture of benzene and toluene.
Another feature is that the volume is an ideal solution is an appropriate summation of the volume of constituent components. In non-ideal solution, the sum of the volume of pure solute and pure solvent is not the same with the volume of the solution.
Nature koligatif solution
Dilute aqueous solution shows properties that depend on the collective effect of the number of solute particles, called koligatif properties (from the Latin word colligare, "gather together"). Koligatif properties include vapor pressure drop, increasing the boiling point, freezing point depression, and symptoms of osmotic pressure.
Types of solution
Solution can be classified for example according to the phase of the solute and solvent. The following table shows examples of solutions based on the phase components.
Sample solution of dissolved substances
Solid Liquid GasSolvents Air Gases (oxygen and other gases in nitrogen)
Water vapor in the air (humidity)
The smell of a solid arising from the dissolution of these solids in the air molecules
Carbonated water fluid (carbon dioxide in water) ethanol in water; a mixture of various hydrocarbons (petroleum)
Sucrose (sugar) in water, sodium chloride (table salt) in water; gold in mercury amalgam
Solid hydrogen is soluble in metals, such as platinum
Water in the active charcoal; moisture in wood
Alloy metals such as steel and duralumin
Based on its ability to conduct electricity, a solution can be distinguished as a solution of electrolyte and non-electrolyte solution. Electrolyte solution containing an electrolyte that can conduct electricity, while the non-electrolyte solution can not conduct electricity.
http://id.wikipedia.org/wiki/Larutan
Solution is a homogeneous mixture (same composition), all the same (particle size), there is no boundary between the solvent with the solute (can not distinguish directly between the solvent-solute), the constituent particles of the same size (both ions, atoms, or molecules) from two or more substances. In the liquid phase solution, the solvent (solvent) is a liquid, and dissolved substances in it called solutes (solutes), can form solid, liquid, or gas. Thus, the solution = solvent (solvent) + solutes (solutes). Especially for the liquid solution, the solvent is the largest volume.
There are 2 reactions in solution, namely:
exothermic, the process releases heat from the system to the environment, the temperature of the reaction mixture will rise and the potential energy of chemical substances in question will fall.
endothermic, which absorbs heat from the environment into the system, the temperature of the reaction mixture will decrease and the potential energy of chemical substances in question will rise.
Solution can be divided into 3, namely:
An unsaturated solution is a solution containing solutes (solute) is less than that required to make a saturated solution. Or in other words, the solution of which the particles are not exactly run out to react with the reagent (still can dissolve substances). Unsaturated solution when the time occurs when the ion concentration
Based on the extent of the solute, the solution can be divided into 2, namely:
The concentrated solution is a solution containing relatively more solutes than the solvent.
Aqueous solution is a solution of relatively fewer solutes than the solvent.
In a solution, the solvent can be water and without water.
Concentration of Solution
Concentration of the solution can be distinguished qualitatively and quantitatively. Qualitatively, the solution can be divided into a concentrated solution and dilute solution. In dilute solution, a solution of mass equals the mass of the solvent because of the density of the solution equal to the density of the solvent. Quantitatively, solution concentration is distinguished by the unit. There are several dissolution process (principle of solubility), namely:
Fluids
Liquid solubility in liquids is often stated "Like dissolver like" meaning liquid substances which have similar structures will be mutually dissolve each other in every comparison. Examples: hexane and pentane, water and alcohol => H-OH with C2H5-OH. Polarity difference between the solute and solvent effect is not big on solubility. For example: CH3Cl (polar) with CCl4 (non-polar). The solution is due to the occurrence of inter-action style, through dispersion forces (the events in the spread of the solute in solvent) is strong. Here solution events, namely the events surrounding solvent particles (confined) particles dissolved. For the solubility of the liquids is influenced also by hydrogen bonding.
b.Solid-liquid.
Solids generally have limited solubility in this fluid due to attractive force between molecules solids with solids> solids with liquids. Solids non-polar (slightly polar) great solubility in low polarity liquid. Examples: DDT has a structure similar to DDT CCl4 so easy to dissolve in non-polar (eg coconut oil), not easily soluble in water (polar).
Gas-liquid
There are 2 principles that affect the solubility of gases in liquids, namely:
The higher the melting point of a gas, liquid has come closer to an attractive force between molecules. Gas with higher melting point, solubility is greater.
The best solvent to a gas is an attractive force between the solvent molecules are very similar to the one owned by a gas. The boiling point of the noble gases from the top down in a periodic system, the higher, and greater solubility.
Effect of temperature (T) and pressure (P) against the solubility, ie temperature increase profitable endothermic process, whereas temperature lowering favorable exothermic process. The process of solid solubility in liquids generally lasts endothermic solubility consequently raise the temperature rise. The process of gas solubility in liquid lasted exothermic effect increases temperature lower solubility.
Dissolution process is considered the equilibrium
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Tools and Materials
Measuring cup
Balance analytical
Glass watches
Pipette drops
Beaker glass
Work Steps
Make 100 ml of HCl 37 % 2 M
Known:
ρHCl : 1,16 kg/L = 1,16 *1000 g/L
Mr HCl: 36,5
So,
nHCl 37% = (0,37 * 1,16 * 1000) / ( 36,5)
= 11,76 mol.
M HCl 37% per Liter = (11,76 mol)/(1L)
= 11,76 M
To make HCl 2M for the quantity of 100 mL is :
V1.M1 = V2.M2
11,76 M. V1 = 2M. 100 mL
V1 = ( 2M.100 mL ) / (11,76M)
= 17,01 mL.
Take 17,01 ml of HCl 11,76 M with a pipette
Enter in a measuring cup
Add the water, until the volume to 100 ml
Make 25 ml of HCl 0.1 M of HCl 2 M
V . M = V’ . M’
V = 0,025 L
M = 0,1 M
M’ = 2 M
0,025 L . 0,1 M = V’ . 2 M
0,0025 = 2 V’
0,00125 L = V’
V’ = 1,25 ml
Take 1.25 ml of HCl 2 M with a pipette
Enter in a measuring cup
Add the water, until the volume to 25 ml
Make 25 ml of NaOH 1 M
Mr NaOH = 23+16+1 = 40
volume NaOH = 25 mL = 0,025 L
mol
Molaritas = ---------------
volume
mol NaOH = molaritas x volume = 1 x 0,025 = 0,025 mol
massa
mol = --------------
Mr
massa = mol x Mr = 0,025 x 40 = 1 gram
Consider 1 gram of NaOH with balance analytical
Input it to the measure cup
Add the water, until the volume to 25 ml
Make 25 ml of NaCl 0,5 M
c = n / V
c = molarity (M)
n = mol
V = volume (L)
n(NaCl) = c(NaCl) x V(NaCl) = 0.5 M x (25/1000)L
n(NaCl) = 0.0125 mol
So, use the formula;
n = m / M
n = mol
m = mass (g)
M = molar
m(NaCl) = n(NaCl) x M(NaCl) = 0.0125 mol x 58.5 gmol^-1
m (NaCl) = 0,73125 g
Consider 0,73125 gram of NaCl with balance analytical
Input it to the measure cup
Add the water, until the volume to 25 ml
Data
Solution of HCl 0,1 M Solution of NaOH 1 M
Solution of NaCl 0,5 M
VI.Discussion
In the making solutions experiments, aiming to find out how to make the solution. Among them 37% solution of HCl 2 M, 0.1 M HCl, 1 M NaOH, and NaCl 0.5 M. but because the lab is not available concentrated HCl then in practical implementation is not made 37% HCl 2 M. Solution is a homogenous mixture. A mixture is said homogeneous if there is no field of inter-component boundaries so that no longer distinguishable despite using ultra microscope. In addition, the homogenous mixture has the same composition in each part.
The first solution was made 0.1 M HCl, which is made from HCl 2 M. working with the following steps take 1:25 ml of HCl 2 M with a pipette, and then enter in a measuring cup and add the water, Until the volume to 25 ml. The principle used in making this solution is dilution, which is used as an ingredient solution is making the same solution but has a larger molalitas, to determine the number of HCl 2 M is required, we need to use the equation as follows,
V . M = V’ . M’
V = 0,025 L
M = 0,1 M
M’ = 2 M
0,025 L . 0,1 M = V’ . 2 M
0,0025 = 2 V’
0,00125 L = V’
V’ = 1,25 ml
From he above equation we can determine the number of HCl 2 M is required, as many as 1.25 ml.
HCl 2 M HCl 0,1 M
Experiments have been performed subject to change, not in accordance with the instructions given, if in the Learning Guide is written to make 25 ml, but the lab work performed made solution of 100 ml, as shown in the pumpkin peck on top. That is because the limitations of the tools used, measuring cups that are available do not have a scale of 25 ml, making it difficult to measure the volume of solution. In the process of mixing, according to the lab that have been conducted, the first step is to take 5 ml HCl 2 M in the measuring cup, then mix it with a little water, then poured into 100 ml measuring flask slowly through the tube wall. Then just add water slowly, keep the water through the tube wall and are not contained directly in the solution. Until the volume reached 100 ml.
The second solution made of 25 ml of NaOH 1 M, with the following working steps Consider 1 gram of NaOH with analytical balance, then input it to the measure cup and add the water, Until the volume to 25 ml. determining the amount of NaOH used, based on the following formula,
Mr NaOH = 23+16+1 = 40
volume NaOH = 25 mL = 0,025 L
mol
Molaritas = ------------
volume
mol NaOH = molaritas x volume = 1 x 0,025 = 0,025 mol
massa
mol=--------
Mr
massa = mol x Mr = 0,025 x 40 = 1 gram
From the equation above we can determine that in order to make 25 ml of NaOH 1 M NaOH needed 1 gram of solid.
NaOH padat Solution of NaOH 1 M
In accordance with the picture above, which used solid NaOH crystal form, so that in a lab that has been done, the first step undertaken was to weigh as much as 1 gram of NaOH crystals using an analytical balance. In weighing exactly 1 gram can not, due to a crystalline form of NaOH does not allow praktikan to reduce / increase the weight of NaOH in small amounts. Then NaOH crystals incorporated into the measuring cup and added with a little water, dissolution aids by stirring with glass rod, until completely dissolved. Then move it slowly in a glass beaker, the next step by flowing water through the walls slowly, reaching a volume of 25 ml.
Final solution made of 25 ml of NaCl 0.5 M, with the following first working step Consider 0.73125 grams of NaCl with analytical balance, then input it to the measure cup and add the water, Until the volume to 25 ml. In determining the amount of NaCl is needed in making this solution, we use the following equation,
c = n / V
c = molarity (M)
n = mol
V = volume (L)
n(NaCl) = c(NaCl) x V(NaCl) = 0.5 M x (25/1000)L
n(NaCl) = 0.0125 mol
So, use the formula;
n = m / M
n = mol
m = mass (g)
M = molar
m(NaCl) = n(NaCl) x M(NaCl) = 0.0125 mol x 58.5 gmol^-1
m (NaCl) = 0,73125 g
From the above equation we can determine the required amount of NaCl, which is about 0.73125 g.
NaCl powder Solution of NaCl
NaCl is a compound of salt, so it is not dangerous when exposed to hand. In a lab that has been dilaksakan as follows, first by weighing approximately 0.73 grams of sodium chloride powder, then add the water slowly through a glass wall to reach the volume of 25 ml.
VII.Conclussion
Making an solutions can be done by : Determine the amount of main materials with suitable formula. For instance: M= gr/(Mr ) x 1000/(v ) or V1 . M1 = V2 .M2. Then, mix it with aquades until needed volume.
Reference
http://id.wikipedia.org/wiki/Larutan
http://edukasi.kompasiana.com/2009/12/18/kimia-larutan-kimia-dasar/
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