THE MOLE A mole (symbol Mol) is the base unit of quantity of a substance in the metric system. A mole is the quantity of a substance that contains 6.02 x 1023 units. A "unit" is the smallest measurable entity in the substance‚ generally either an atom or a molecule. The number of units in a mole was determined by Italian chemist (a scientist specializing in the composition‚ structure‚ properties‚ and reactions of matter) Amedeo Avogadro (1776-1856)‚ one of the founders of modern physical chemistry
Premium Atom Molecule Avogadro constant
Majed Al Dhwaihi Chem 151 Lab Prelab Assignment for week 3 Chemical Separation Procedure: Separating the sample: First place a small amount of the spinach provided in the mortar‚ just enough to cover its bottom; combined with the sand provided to break down the call walls. A 1:1 mixture of hexane and acetone was determined to best solvent for this extraction. Knowing this add one mL of the pure hexane and one mL of the pure acetone to the mortar. Grind the contents until the cell walls
Premium Solvent Separation process Mixture
Submitted: June 10‚ 2015 Title: Observations of Chemical and Physical Changes Purpose: the purpose of this lab experiment is that I will be able to decipher the difference between a chemical and physical change. I will be about to tell whether a chemical change has occurred during the experiment or if it was a physical change and I will be able to answer why it is either one. Procedure: In the lab experiment‚ I mixed different types of chemicals with different background to see if there was a chemical
Premium Chemistry Chemical reaction Hydrochloric acid
The Lab Report‚ Significant Figures & Working with Numbers CHMY 142-18 Experiment 1 September 4th‚ 2009 Introduction: This experiment is dealing with the relative accuracy of an individual measurement. Data will be provided to perform the calculations asked for. The purpose of this experiment is to know how to use significant figures and to get formularized with making proper laboratory reports. Procedure: Use the data table’s information to solve the missing
Premium Temperature Volume Density
Pos t-Lab Data Summary Note : some questions will display a variable like "nCount" or "SyInput" instead of an actual number in the data summary. Q# Question Text 5) Data Entry - No Scoring Enter the precise mass in GRAMS of the potassium iodate used to prepare your primary standard solution. Your mass precision should be reported to a thousandth of a gram‚ i.e. 0.302. (Use 3 significant figures.) Your Answer: 0.536 No Points Possible 6) Scoring Scheme: 3-3-2-1 If one had weighed out precisely
Premium Titration Iodine Sodium
Question 1 (Limiting Reagent) 15.00 g aluminum sulfide & 10.00 g water react until the limiting reagent is used up. [Atomic mass: H = 1.008‚ Al = 26.98‚ S = 32.07‚ O = 16.00] Here is the balanced equation for the reaction: Al2S3 + 6 H2O ( 2 Al (OH)3 + 3 H2S (i) Which of the two reactants is the limiting reagent? (ii) What is the maximum mass of H2S which can be formed from these reagents? (iii) How much excess reagent remains after the reaction is complete
Premium Sodium Reagent Stoichiometry
D_____ J_____ CARBOHYDRATES LAB May 22‚ 2013 Pre-lab Questions 1. The water in test tube No. 1 is a negative control. No reaction is expected to occur because water is not a carbohydrate. Reaction by a negative control is evidence of contamination. 2. The color changes expected for positive test results are Benedict’s test: orange to brick red Tollen’s test: metallic silver Starch iodine test: blue-black 3. Identify each of the samples in Part 1 as monosaccharide
Premium Glucose Disaccharide Carbohydrate
Investigating the Determining Characteristics of Cations and Anions Chem 111 Sec 560 Introduction: The purpose of this lab was to study the specific characteristics of cations and anions‚ and ultimately to be able to identify an unknown substance based on our studies and tests using the logic trees developed through the experiment. A logic tree is a graphical display of the findings from this lab which‚ through a series of yes/no questions‚ elimination tests
Premium Solubility Ion Sodium chloride
Experiment 2: The Effect of Different Reactants on the Type of Gases Produced Abdul Aziz Malik Submission Date: 18th April 2012 Background Information In the experiment‚ when oxygen is being tested‚ a glowing splint will be used and when that splint is placed in to the mystery gas and the splint reignites‚ then the gas is oxygen. When hydrogen is being tested‚ a burning splint will be used and when the splint is placed in to the mystery gas and a “pop” sound occurs‚ then the gas is hydrogen
Premium Oxygen Chemistry Water
Gabriel Alizaidy Liquid Chromatography September 14‚ 2009 Objective: To separate the components of unsweetened‚ grape flavored Kool-Aid. Procedure: Using two syringes‚ inject different concentrations of alcohol to extract red and blue dyes‚ and artificial flavoring. Data: Conclusion: Different dyes are shown when separated by different concentrations of isopropyl alcohol. Discussion of Theory: Chromatography‚ resolution and selectivity played major roles in making the experiment work
Premium Chromatography Chemical polarity Separation process