Colligative properties are the physical changes that happen when you put a solute in a solvent. The ratio of the number of solute particles are a contributing factor, but not the types of particles. There are four main properties that are affected by this solute mass ratio, which include depression of freezing point, elevation of boiling point, lowering in vapor pressure, and osmotic pressure.
Every kind of liquid basically has a freezing point, they just vary in temperature. Water for instance, has a freezing point of 0℃ or 32℉. If you add a solute to water though, the solute molecules disrupt the formation of the crystals. In freezing point depression, when you put a solvent in a solution it lowers its freezing point. For instance, if you put an X amount of salt in water and an X amount of sugar in the same amount of water, they both will have a lower freezing point compared to pure water. The salt, however, will have a lower freezing point than the sugar because the salt has more to particles to disrupt the crystals forming in weight than sugar does in weight.
When we see people putting salt on
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30). In other words, it is the pressure required to achieve osmotic equilibrium thus stopping osmosis. Osmotic pressure, like the other three Colligative Properties, depends on the amount of solute that is present in the solvent. One must consider the concentration of the solvent in a solution. When you add a solute to a solvent, the concentration is lower than it is for the pure solvent. Solvents will flow from an area of high concentration to an area of low concentration. So, the more solute put in a solvent would impose more molecules that make the concentration lower, which thus would make the pressure increased, because there would need to have increased applied pressure to stop
The side of the membrane that has the higher concentration is said to have the concentration gradient. It drives diffusion because substances always move down their concentration gradient. The pressure gradient also plays a role in diffusion. Where this is a pressure gradient there is motion of molecules. The pressure gradient is a difference in pressure between two different points.
Cations are positively charged ions, which are attracted to their negatively charged counterparts, anions. Precipitates can form when these cations and anions combine in aqueous solutions; however, precipitates only form if one of the products of the chemical reaction is not soluble in that solution. Solubility is instrumental in understanding how precipitation reactions occur. This is because solubility rules, determine whether a precipitate can form. A precipitate can form if the cation in the compound is soluble when combined with an anion. For example when the solutions silver nitrate and sodium chloride (reactants) are mixed, silver chloride and sodium nitrate (products) are formed. Following the solubility laws, silver nitrate is the precipitate, as it isn’t
The purpose of this lab was to determine the density of water and an unknown liquid, along with a rectangular solid and an irregular shaped solid. In this lab, the relative density was calculated and then used to make an educated guess on the substance. Density is the relationship between the mass of a substance and the amount of space taken up. This measurement is influenced by the mass of atoms, the size, and how they are arranged. The density of the four objects was determined by using the mass (g) and volume (mL or c3). Mass is the property of matter that measures its resistance to acceleration. In addition, volume is the amount of space that a substance or object occupies. Finally, the mass (g) was divided by the volume (mL or c3) to find the final density (g/mL or c3).
In osmosis, water can travel in three different ways. If the molecules outside the cell are lower than the concentration in the cytosol, the solution is said to be hypotonic to the cytosol, in this process, water diffuses into the cell until equilibrium is established. If the molecules outside the cell are higher than the concentration in the cytosol, the solution is said to be hypertonic to the cytosol, in this process, water diffuses out of the cell until equilibrium exists. If the molecules outside and inside the cell are equal, the solution is said to be isotonic to the cytosol, in this process, water diffuses into and out of the cell at equal rates, causing no net movement of water. In osmosis the cell is selectively permeable, meaning that it only allows certain substances to be transferred into and out of the cell.
It is the ratio of distance travelled by solute and the distance moved by solvent.
If the concentration of sucrose increases, then the mass of the potato will decrease. However, if the concentration of the solution in the beaker is less than that of the potato (such as distilled water), then the mass of the potato will increase. So, as the concentration of sucrose increases the rate of osmosis increases.
Most cell membranes are like that, being permeable to water and some solutes only. Osmosis is therefore the diffusion of water through a partially permeable membrane. The basic principles of diffusion apply here.
The temperature probe was placed into the test tube and recorded the temperature of the freezing solution using Logger Pro software. The test tube was held against the inner glass of the ice bath beaker so the test tube was visible to see when the solution froze over. Once the freezing point was measured, the temperature stopped being monitored and the data was recorded. The steps mentioned above for finding the freezing point, also known as ΔTf, was replicated for the 0.0, 0.4, and 0.6 concentrations. To find the freezing point depression, the equation ΔTf = imKf was used. The molality (m) of each solution was then calculated dividing moles of solute by kilograms of solvent, and the Kf value for magnesium chloride is known to be -1.86. Since magnesium chloride breaks down into three ions in deionized water, it was concluded that the Van’t Hoff factor couldn’t exceed three. For better accuracy, the experiment explained above for finding the freezing point depression and Van’t Hoff factor was re-conducted exactly the same to determine more accurate results. Again, the molality of each solution was calculated, and a graph expressing the change in freezing temperature verses molality
The first factor is the concentration. The concentration rate is decided whether how strong the solution is. For an example, if there is a lot of hydrochloric acid, and sodium thiosulphate, then there is a high chance that the reactions will occur. If there is a solution that is neutral, it would slow down the process of the reaction. The second factor is the size of the particles.
π is equal to the osmotic pressure, V is equal to the cell volume and B is the intracellular solids (Hall). Ponder’s R value is the ratio of intracellular solvent volume to the water in its environment; R=(Vi -b)/W. These two equations are related because Ponder’s R value is a measure of how much of an osmometer a cell is while the van’t Hoff relation shows what the osmotic pressure is, both inside and outside the cell. Overall cell membrane permeability can be measured by Ponder’s R value while the osmotic pressure differentials between the external environment and the internal environment are seen with the van’t Hoff relation (Hall). Cells evolved to become great osmometers, but not perfect osmometers, in order to provide a way for solutes to move along permeable membranes. The van’t Hoff relation permits organisms to live in environments of varying osmolarity because regulating solute concentration within a cell can increase or decrease the cell’s affinity for osmosis (Darnell et al). Ponder’s R value, on the other hand, shows how a cell can never become a perfect osmometer. If a cell could become a perfect osmometer, it could cause cell lysis or shrinkage of the cell (Hall). The avoidance of perfect osmometry can be seen within the human erythrocyte as a small portion of cell water will not take part in an osmotic exchange due to tonicity within its
Introduction: A phase change is a result from the kinetic energy (heat) either decreasing or increasing to change the state of matter (i.e. water, liquid, or gas.) Thus saying, freezing is the phase change from a liquid to a solid which results from less kinetic energy/heat. Also, melting is the phase change from a solid to a liquid which results from adding kinetic energy/heat. So, the freezing and melting point of something is the temperature at which these phase changes occur. Therefore, a phase change will occur when a vial of 10 mL of water is placed into a cup of crushed ice mixed with four spoonfuls with 5 mL of sodium chloride for 30 minutes. If 10 mL of water is placed in an ice bath, it will then freeze at 5 degrees Celsius because the kinetic energy will leave quicker with the ice involved. The purpose of this lab is to observe what temperature the water must be to undergo a phase change.
These phases can go from one to another when affected by certain things, which is known as phase changes. To switch from a solid to a liquid, the solid must melt. On the other hand, to switch from a liquid to a solid, freezing must occur. Furthermore, to switch from a liquid to a gas, a process known as evaporation must take place. In contrast, to go from a gas to a liquid, condensation must take place. Furthermore, sublimation must take place for a solid to turn to a gas. Inversely, deposition must occur for a gas to change to a solid.
There are three main variables that determine whether a liquid will posses capillary action. (Davis, 1995)
molecules its size it would have a boiling point of -75øC and a freezing point of -125øC4.
Most elementscrystalize as metals. Some solids can also be frozen liquids. The atoms in a solid are tightly bonded which means it has a definiteshape. The second phase of matter is liquids.