6. Wash, dry and observe under oil immersion lens. Differential stains render one type of microbe one colour and other types of microbes another colour. In the Gram stain, Gram positive organisms retain the primary dye complex (crystal violet-iodine) whereas Gram negative cells loose the primary dye complex during the challenge rinse. Most differential stains have a challenge step that follows staining with a primary dye.
This is because tap water’s pH level is just over neutral (base). When vinegar is added to the cabbage, the cabbage will turn red. This is because there is a pigment (coloured chemical) in the red cabbage that acts as a pH indicator. Neutral Red Neutral Red is a dye used for staining histology (study of tissue under a microscope). Neutral Red also can be used as practical jokes.
If the soil is too acidic - the most common complaint - it is treated with a base (chemicals opposite to an acid) in order to neutralise it. Common treatments use quicklime (calcium oxide) or chalk (calcium carbonate). Indigestion We all have hydrochloric acid in our stomach - it helps breakdown food! However, too much acid leads to indigestion. Therefore, to cure this ailment we need to neutralise the acid with a base such as, sodium hydrogen carbonate (baking soda), or an indigestion tablet.
Hypothesis; Using the method of titration, I can neutralize an alkaline by the vinegar; dilute ethanoic acid, and the volume of acid that neutralized the base contains the exact mass of the pure ethanoic acid in the impure vinegar. Apparatus; -a burette -a conical flask - two beakers - retort stand - Vinegar (9 grams per dm3) -sodium hydroxide solution -pipette -phenolphthalein -dropper Procedures; a) I filled the burette with vinegar up to zero mark. b) Using a pipette, I measured 25cm3of sodium hydroxide and transferred this into a conical flask. c) I added two drops of phenolphthalein in the conical flask. The color of the base is now orange.
Lab 2 – Water Quality and Contamination Experiment 1: Effects of Groundwater Contamination |Table 1: Water Observations (Smell, Color, Etc.) | |Beaker |Observations | |1 | | |2 | | |3 | | |4 | | |5 | | |6 | | |7 | | |8 | | POST LAB QUESTIONS 1. Develop hypotheses on the ability of oil, vinegar, and laundry detergent to contaminate groundwater. If vegetable oil is placed in water, will I be able to remove it? Will it be safe to consume?
Lab 2 – Water Quality and Contamination Experiment 1: Effects of Groundwater Contamination |Table 1: Water Observations (Smell, Color, Etc.) | |Beaker |Observations | |1 |Slightly cloudy, unknown chemical smell | |2 |Oil and water do not mix | |3 |No detectable difference other than vinegar smell. | |4 |Soap settles to the bottom of the beaker until stirred. Heavy soap | | |scent. | |5 |Slight cloudiness and dirt particles, no odor | |6 |Water is darker with more sediment.
What is a peroxide killer? After bleaching the cellulosic fiber with hydrogen peroxide, the fiber is subjected a thorough hot wash cold wash and neutralization processes. These operations would remove all superficially available chemicals that were used in bleaching process. However in practice it is found that the core alkali i.e. the alkali due to the use of caustic soda or soda ash and hydrogen peroxide, wetting agents and other auxiliaries would remain in the core of the fiber processed even after 2 or 3 washes.
Oil of vitriol, also known as sulfuric acid .Sulfuric acid? What is it? Sulfuric acid is a highly corrosive strong mineral acid with the molecular formula of H2 SO4. It's a colorless or slightly yellow liquid which is soluble in water at all concentrations. Sometimes, it could be dark brown by being dyed during its industrial production process in order to alert people to its hazards.
Dip the slide into Eosin solution for 7 times and remove the excessive solution with a paper towel. 3. Dip the slide into new methylene blue for 9 times and remove the excessive solution with a paper towel. 4. Use the incinerator to allow it to dry completely.
Using a thin-layer chromatography, or TLC, the position in which molecules stop advancing upwards could be observed. By applying the TLC method to this experiment, different traveling distances of a certain chemical, with changing salt concentrations of water, can be measured. In this investigation, however, sheets of tissue papers were dipped into salt water with different concentrations and soaked until the water traveled to the top, so the method was different from the TLC experiment. Consequently, the volume of liquid absorbed will likely not change with different salt concentrations since every time the paper will be dipped into the solution until it completely absorbed water, each time in the same manner. Moreover, the mass of solution absorbed will increase because the density of the solution increases with increasing concentration.