Background Research- How Salty Does the Sea Have to Be for an Egg to Float? Density is the mass of a material per volume: ρ = | m v
Name: ___________________________________ Date: ______________ Practice Test #3 ____ 1. When a precipitation reaction occurs, the ions that do not form the precipitate A) evaporate B) are cations only C) form a second insoluble compound in the solution D) are left dissolved in the solution E) none of these 2. An aqueous solution of potassium chloride is mixed with an aqueous solution of sodium nitrate. The complete ionic equation contains which of the following species (when balanced in standard form)? A) B) C) D) E) ____ 3.
Litmus test: Red turned blue and blue had no reaction Dilute HCl: Fizzes and substance turns yellowish while bubbling the back to white. Dilute NaOH: Dissolves and substance became a bit thick Substance: CuCO3 Color: Green Odor: Yes Effect of Heat: Turned into black powder Solub. or Reaction w/cold H2O: No reaction. Solub. or Reaction w/hot H2O: No reaction Litmus test: No change on blue or red.
The vinegar removes these minerals, and the shell becomes soft, allowing the egg to bounce without breaking the shell. The eggshell is made from calcium carbonate. When the egg is subjected to prolonged exposure of the vinegar [an acetic acid], the vinegar reacts with the calcium carbonate of the shell by breaking it into calcium, and carbon dioxide gas, eroding the shell. The eggshell is thin, brittle (easily breaks), has an exterior covering of an egg. By the time the egg is done you will see egg yolk sloshing around as you shake it (rub the egg gently to see the yolk but don’t rub too hard or it will pop).
Liz Somone Chem 112 TA: Meng Floating Egg Lab Report The goal of this experiment was to determine the density of a solution needed to float an egg, the freshness of an egg, and the way volumetric glassware affects the value and accuracy of density. The types of volumetric glassware used were a 25-mL buret, 25-mL Mohr pipet, 25-mL volumetric pipet, 25-mL volumetric flask and a 25-mL Erlenmeyer flask. I prepared a 1500 mL solution of salt and water in order for the egg to float. Using that same solution I filled a buret that was mounted vertically to the 0 and then drained the solution to nearest 0.00 mL. The solution was then drained into an Erlenmeyer flask and I recorded the weight of the flask before (W1) and after the solution (W2) and then subtract the weight of the flask with the solution from the weight of the flask alone in order to find the absolute mass of the solution (W3).
4. Calculate the molarity of the commercial bleach (not diluted) using your answer from step 3 and the M¬1V1 = M2V2 equation. (Use volume of concentrated bleach and total volume of dilute bleach) 5. Assume that the density of the commercial bleach is 1.08g/mL. Calculate the percent by mass of NaClO in the commercial bleach.
Hydrate Lab The purpose of this lab is to analyze the percent water in a crystalline hydrate and to indentify the hydrate from a list of possible unknowns. The solid hydrate will be heated to remove the water, and the percent can be found by measuring the mass of the solid before and after heating. The hydrate will be indentified by comparing the percent water in the hydrate with the percent water calculated for the possible unknown. Before the lab there are pre-lab questions: 1. Describe the three general safety rules for working with a Bunsen burner.
Tablet | A report based on a scientific experiment designed to investigate and compare the rates at which different forms of aspirin dissolve. | 11-11-2013 | Introduction This experiment was designed to investigate and compare the rates at which different aspirin tablets dissolve in both Water (H2O [representing saliva]) and Hydrochloric Acid (HCl [representing the stomach’s acid]). The amount of Water and Hydrochloric Acid will be kept constant between tablets, and tests. Aim To investigate and compare the rates at which different Aspirin Tablets dissolve. The different kinds of Aspirin tablets are: * Enteric Coated Tablets * Capsules * Regular Tablets * Dissolving Tablets.
Observing Changes – Materials & Procedures Materials Water Copper (II) sulphate (Powder) Copper (II) sulphate solution Iron nail Sodium carbonate Hydrochloric acid Magnesium ribbon Flame (candle) Sugar Aluminum foil Test tubes Test tube rack Tongs Medicine dropper Spoons Beakers Safety goggles Scoopulas Procedures Water and Copper (II) Sulphate Procedure 1. Add a small amount of solid copper (II) sulphate to a test tube with a scoopula. Record the physical properties. 2. Write a hypothesis on what you think will happen when water is added.
The acid was poured into the flask until there was a permanent pink colour. The acid was allowed to be poured for a little longer before the flask was removed and taken to a lab bench with a buret that contained 0.1 M sodium hydroxide, and the amount of acid used was recorded. The sodium hydroxide was added into the flask in small amounts