D) the absence of charged molecules inside cells. Answer: C Page Ref: Section 3 11) The ________ pressure is the pressure required to prevent the flow of solvent through a solvent-permeable membrane that separates two solutions of different solute concentration. A) hydrostatic B) electromotive Answer: C Page Ref: Section 3 12 C) osmotic D) partial 12) Which is true about the solubility of electrolytes in water? A) They are all insoluble in water. B) They are usually only sparingly soluble in water.
In this experiment, the hydrate was separated into water and the anhydrous salt. However, when the masses were combined the overall mass remained constant. In order to find the percent composition, the masses of the water and the anhydrous salt had to be identified. Without these components, it would be impossible to find the percent composition of the water in the hydrate. The empirical formula is the simplest formula of a compound.
According to Science Buddies in the article Measuring Surface Tension of Water with a Penny, water “molecules at the surface experience a net force pulling them inward” (2007). For instance, if you filled a cup with water to the very top, adding a few more drops of water will make the glass overfill without spilling any actual water because the water molecules are being pulled inward. While water has a unique, high surface tension, other liquids, like olive oil, do not. The cause of low surface tension in olive oil is due to “Van Der Waal” forces. While hydrogen bonds have a uniquely high surface tension, van der Waals forces have a relatively weak attraction, which causes low surface tension.
The separation of cyclohexene could not depend on distillation alone. The method used in our experiment is one way that we could employ to separate azeotropes into its constituents. By adding a chemical that could form complex with one of the component, in our case, CaCl2 forms complex with water,
Next the freezing point which didn’t eliminate either of them. Next we look at the mass which was 7.465g/ml. This make me lean toward ethyl ether but the masses were still pretty close. Next we move to the solubility of the substances. They are both very soluble in alcohol and hexane so that doesn’t help, but in water ethyl ether is semi soluble and pentane is in soluble.
Vegetable oil is hydrophobic and there for is not water soluble but alcohol on the other hand is completely soluble with vegetable oil. 3. We know from observing the vegetable oil and water together that the relative density of water is greater then the density of vegetable oil because the oil will always recede to the surface of water. 4. Emulsification agents allow for two unbendable liquids to be combined, the detergent hold properties that both substances can in return blend with leaving detergent dissolving in both the water as well as the alcohol unlike other substances we tried to
Part E – Deriving a solubility curve Aim: To be able to calculate the solubility of the compound in a certain amount of water as the temperature increases or decreases. Hypothesis: As the water increases, the solubility decreases and the substance’ saturation would get lower. And as the volume increases, the substance won’t separate to the water anymore which makes it dissolved forever without getting crystallized when the water cools down. Apparatus & Method: [refer to the sheet p. 64] Result: Temperature | Volume [ml] | Solubility [g/100g] | 65 ̊ C | 5 ml | 130.44 g | 46 ̊ C | 8 ml | 81.525 g | 39 ̊ C | 11 ml | 59.29 g | 28 ̊ C | 14 ml | 46.586 g | 22 ̊ C | 17 ml | 38.36 g | 16 ̊ C | 20 ml | 32.61 g | 12 ̊ C | 23 ml | 28.35 g | 12 ̊ C | 26 ml | 25.08 g | The solubility was calculated with the formula of: Solubility=6.522gml of waterx 100 The solubility of Potassium Nitrate is directly affected by the temperature of the solution. As the temperature of the solution rises, the solubility of Potassium Nitrate increases.
From this information, the percentage of salt verses water ions can be determined Ions are also produced in the liquid or solid state when salts interact with solvents (for example, water) to produce "solvated ions," which are more stable, for reasons involving a combination of energy and entropy changes as the ions move away from each other to interact with the liquid. These stabilized species are more commonly found in the environment at low temperatures. A common example is the ions present in seawater, which are derived from the dissolved salts. Procedure Obtain 250 mL beaker Weigh dry 250 mL beaker and record weight. Add 10mL of unknown salt and water solution.
Calorimetry 23.04.2011 Introduction: An experiment to determine the efficiency of thermal energy gained while heating water by burning alcohol. Aim: To calculate and analyse the efficiency of the energy transfer when heating water in a calorimeter. Hypothesis: There will be an energy transfer when the alcohol is burned to heat the water. Materials: • Clamp • Spirit burner • Scales • Thermometer • Calorimeter • 30cm3 distilled water Method: • The clamp was set up to hold the calorimeter. • 30cm3 of distilled water was poured into the can.
The standardization of of KMnO4 solution with Na2C2O4 is as follows: Oxidation: Na2C2O4→2Na++2CO2+2e- Reduction: KMnO4+8H++5e-→K++Mn+2+4H2O And the overall balanced equation: 16H++5Na2C2O4+ 2KMnO4→10Na++2CO2 These reactions are thermodynamically spontaneous, but the final one is susceptible to a side reaction and it is naturally very kinetically slow (Blandamer et al. 1998). The MnO2 present in the reaction in KMnO4 must be filtered to remove it because it interferes with the