In acidic aqueous solution, a buffer is formed by the dissociation of the acid: HA ⇄ H+ + A- Hence, when acid is added, the excess H+ reacts with the A- to form more HA, lowering the pH and minimising the effect of the addition of acid. When alkali is added, the OH- reacts with the dissociated H+ to form water, which reduces the effect of the alkali by restoring the pH to normal levels. Alka Seltzer acts as a buffer because the citrate ions in solution (C6H5O73-) are able to react with H+ when acid is added, to form citric acid, C6H8O7. This neutralises the acid, increasing the pH. The excess HCO3- ions also react with H+ to form CO2 and water, hence lowering the pH and reducing the acidity of the solution. The HCO3- ions also act as a buffer when alkali is added, because they react with OH- to create water and CO32- ions, increasing the pH and reducing the effect of the addiction of alkali.
Utilizing the method that the experimenters have come up with, the procedure isolates the variable being tested, which is the paper towel brand. By not changing other aspects of the procedure, other factors have a lower chance of affecting the accurate results of the answer to the main question. Additionally, the method is a quick and simple experiment, causing no use of excessive time than the provided duration. Within the first minutes of the experiment, the experimenters and the advisor realized that the method did not really provide accurate results due to merely estimating the numbers without the use of a graduated cylinder. Changing that aspect of the procedure by using a graduated cylinder to measure the amounts of water instead helped
First, they collected the materials, then they poured water into each cup in even amounts, next they poured 1/8 of sugar in one, then they poured 1/8 of salt into another. They left one cup with just regular water and sat them in the freezer. They regularly checked to see which one froze the fastest. The sugar water ended up freezing first, before the plain and salt water. The plain water froze second, and in the last place was the salt water.
Experiment A: This lab’s goal was to find out whether tap water or pond water had more tannin contamination. When tannin and chlorine combine, the resulting substance can become a carcinogen. I added a reagent in each sample of water; in this lab, the tannin reagent is used to illustrate if a solution has elevated tannin levels. If the substance has tannin, then the solution will turn blue in about 30 minutes. I used a tannin colorimeter to measure more precisely the concentration of tannin in a substance in parts per million.
Pertaining to the appearance of the oil and water before the reaction occurs, oil “sits” on top of the water because oil is less dense than water, and therefore rests on the surface of the water. The Alka-Seltzer, or effervescent tablet, reacts with the water and produces bubbles of carbon dioxide gas. This gas is less dense than both the water and oil, so it travels the the surface of the liquid, pulling a small amount of the colored water with it and creating the “lava lamp” effect. The chemical reaction that is occurring is an acid-base reaction, and results from the reaction between the ingredients in the Alka-Seltzer tablets.
I settled with 50mL of water, the activator, and 15g of ammonium nitrate, the substance used to chill the water. Each substance was given its own bag, with the water within the smaller bag that sits inside the larger bag containing ammonium nitrate. The bag containing water was
Diet Coke, Fanta and Sprite (all 1.5L) 4 packs of mint Mentos (14 per pack) 2 metre measuring tape Tape Recording device Safety glasses Safety coat Method Put on eye protection goggles and a science lab coat Set up and start recording the experiment on the camera Place the bottle of Cola in a flat outdoor area, at least two metres from any buildings or anything hanging above the area Carefully remove the cap and get the pack of mentos and make sure it lines up with the top of the bottle and squeeze them out carefully but still fast Run back without tipping the bottle over or disturbing the reaction. Record the maximum height of the reaction in the results table Repeat the experiment so each different fizzy has 3 sets of results.
To be able to conduct this experiment multiple materials were needed, and these materials were a measuring cup, a food scale, and 12 oz of the following drinks; water, Pepsi, Root Beer, Sprite, and Mountain Dew. The measuring cup was used to measure the amount of each soda. This was used to make sure that no mistakes were made while setting up the experiment. A food scale was used to measure the weight in ounces of the drinks. This was done to measure the change in weight over time.
Results Dose calculation The energy absorption and dose distribution of microbeam in a homogenous water phantom, half-air/half-water phantom and the voxel-lung models were calculated by MC simulations. The results of all simulations are shown in this chapter. Dose distribution of microbeam in a homogeneous water phantom Figure 14.A shows the dose distribution of MRT in the simple cubic water phantom (5×5×5 mm3). The width of microbeam was 50µm with a center to center space 400 µm.
Determining the percentage of sodium carbonate in a sample of washing soda crystals Aim The purpose of the experiment carried out was to determine the percentage of sodium carbonate (Na2CO3) in a known amount of washing soda crystal, using the titration technique. Acids & Bases Water is the most common acid and base found on earth. An acid is anything that can donate a proton/H+ and a base is anything that can accept a proton/H+ – Bronsted-Lowry. Water being able to both accept and donate a proton/H+ is both an acid and base.
This is a poster about the density of the plastic of a water bottle, it was a group project with 4 people, including myself. We used scientific method and included all that information on the poster. In the lab, we did 3 trials, each with a different piece of a different brand of water bottle, we made a table, a scatter plot, and a bar graph to organize our data and we also calculated the percent error. The table had trails, volume, mass, and destiny on it, the scatter plot was on mass and volume, and the bar graph was on density and trails, all of this data went into the results section of our poster. After we did the lab, we typed out an introduction, methodology, discussion, and a literature cited.
Transfer the ice bucket with melted 0.6% agar to cell culture hood for subsequent steps. 7. Mix 0.6% agar and cell suspension in a 1:1 ratio, preparing a total volume of 12 ml per 6-well plate. 1.5 ml will be required per well but extra should be made as
To start, the first hypothesis was supported. The first hypothesis stated that when the level of water increases, there will be a higher pitched sound when blown over. Bottle C; the bottle with the most water; fifteen and a half centimeters; produced the highest pitched sound. The waves in the bottle reflected between the top of the bottle and the surface of the water which had a seven-centimeter difference, to create a shorter wavelength and higher frequency. Bottle A was filled five and a half centimeters of water which caused the lowest pitched sound.
The leading question in the experiment was how can we manipulate the materials in milk to make the stickiest glue? By altering some of the ingredients and adding others, glue can be made. Depending on what ingredients and the amount being added, the more sticky or less sticky it will be. Based on our background information including all the Ingredients and what they do and how they affect the milk, the hypothesis that made the most sense in this experiment was, if we add more baking soda to the curdled milk, the glue will be stronger. The measurements recorded were set back from a complication.
Introduction: In this lab, of water in a hydrate, or a substance whose crystalline structure is bound to water molecules by weak bonds, is determined by heating up a small sample of it. By heating, the water of hydration, or bound water, is removed, leaving only what is called an anhydrous compound. Based on the percent water in the hydrate, it can be classified as one of three types: BaCl2O ⋅ 2H20, with a percent water of about 14.57%, CuSO4
