Too much water added resulted in a high viscosity and low elasticity. In order for the PVA and borax to turn into solutions, high temperatures were set. Room temperature was not enough to form solutions, which is why a stove was used. The borax solution was the cross-linking agent due to the formation of boric acid, which accepts the OH- molecule in the PVA solution. Hydrogen bonding linked the borax solution and PVA together.
Identify the unknowns by its melting and boiling points. 2. Learn to set up a proper distillation apparatus. Theory: Intermolecular forces play a large part in identifying unknowns when conducting a distillation experiment. The stronger the bond, the higher boiling and melting points will be.
The indicator Phenolphthalein was the substance used to signal when the titration reached the point at which the reactants are stoichiometrically equal as defined by the balance reaction equation. Phenolphthalein is a chemical compound with the formula C₂₀H₁₄O₄ and is often written as "HIn" or "phph" in shorthand notation. Often used in titrations, it turns colorless in acidic solutions and pink in basic solutions. Sodium hydroxide or Hydrochloric acid would not have been as effective or accurate because they would have reacted with the water vapor from the air. In this lab setup, graduated cylinders or beakers were not used.
The variable that affects osmotic pressure is You correctly answered: a. the concentration of nondiffusing solutes. 4. The net movement of water would be into the cell in a You correctly answered: b. hypotonic solution. page 1 Experiment Results Predict Question: Predict Question 1: What effect do you think increasing the Na+ Cl- concentration will have? Your answer : a. increased osmotic pressure Predict Question 2: What do you think will be the pressure result of the current experimental conditions?
Describe and explain the roles of water in living organisms and as an environment for living organisms Water has many different properties than enable it to be easier for organisms to live in. Firstly, water is a great solvent. The importance of this is that the metabolic processes in all organisms rely on chemicals being able to react together in solution. We can see this through many examples for organisms. To start with, there is the transport of nutrients, in glucose and amino acids in the blood.
As it rises, it cools, making it denser and therefore heavier, so it sinks. This all happens in slow motion because heat absorption and dissipation are fairly slow processes, and the density changes we are discussing here are very slight. To create the floating blobs, the two compounds in a motion lamp must be immiscible, or mutually insoluble. All this means is that liquid A doesn't dissolve in liquid B -- the two don't mix, so you see two separate liquids, one floating on top of or within the other. The classic example of immiscible compounds is oil and water.
This method is used because it has two certain advantages, according to Nerdz-Stormes. First, the percentage of quantity of the yield is much higher with this method than if it is just manually pressed. Second, it’s aimed to get a lower boiling point of the liquid by mixing the compound with water. The theory of this distillation process is mixing compounds that contain the aimed product with water to reduce the boiling point of it, so the organic compound does not decomposed by heat. The boiling point can be reduced because of the vapour pressure of it would be the sum of water’s vapour pressure and the compound’s vapour pressure.
In the water molecules, hydrogen is slightly positive and oxygen slightly negative so they are attracted to ions of the opposite charge, known as dipole attraction. These water molecules break apart the bonds of a salt by surrounding themselves around the salt ions, with the opposite charges facing each other. Whether or not a salt dissolves is determined by which attractive force is stronger, the internal ionic force or the attraction for the ions from the water molecules (Ophardt, C., 2003). Potassium nitrate (KNO3) contains negative nitrate ions and positive potassium ions. When potassium nitrate is placed in water the slightly positive hydrogen’s in the water molecule are attracted to the nitrate ions and the potassium ions are attracted to the slightly negative oxygen.
Purpose: I will like to do this experiment to see whether or not soap bubble will float or sink and to develop an understanding of sinking and floating. Materials: * A solution to make soap bubbles * A bubble wand * A large clear container with an open top * ½ cup of baking soda * 1 cup of vinegar * A shallow dish to fit inside a larger container Hypothesis: Soap bubbles will stay afloat longer in carbon dioxide than in air. Background Information: This experiment will focus on a scientific investigation. Its scientific topic is to find out if the soap bubbles will float or sink in the bowl. Conclusion: The hypothesis is that soap bubbles will stay afloat for a longer period of time in carbon dioxide than in air, is proven to be true.
Bottled water has negative and positive effects on the environment and human health. Moreover, the positive outweigh the negative with bottled water. Tap water is filtered from wastes, sometimes it can’t be 100% filtered, according to the U.S. Environmental Protection Agency (EPA)2. Most people think that tap water has the same taste as bottled water, which is incorrect in my opinion. Drinking water from the tap tastes different, and its not a very safe thing to do I believe.