Examination of Water and Wastewater 5210 BIOCHEMICAL OXYGEN DEMAND (BOD)*#(1) 5220 CHEMICAL OXYGEN DEMAND (COD)*#(2) 5220 A. Introduction Chemical oxygen demand (COD) is defined as the amount of a specified oxidant that reacts with the sample under controlled conditions. The quantity of oxidant consumed is expressed in terms of its oxygen equivalence. Because of its unique chemical properties‚ the dichromate ion (Cr2O72–) is the specified oxidant in Methods Section 5220B‚ Section
Premium Sample size Chemical oxygen demand Biochemical oxygen demand
Observation Reflection Paper Tyler Smith Intro to Teaching 4/26/07 Tyler Smith I My passage to becoming a teacher started this spring semester when I started to take the class‚ Introduction to Teaching with Mrs. Eastman. Before taking the class‚ I was not sure if! really wanted to enter the teaching profession. I was inquisitive about the opportunities that I could pursue with the profession‚ but decided to take the class with the best intentions to succeed and get my foot in
Free Teacher Education
Sample Paper – 2012 Class – X Subject –Chemistry Chemical Equations and reactions Very Short Answer (1 marks each) Write the name and formula of compounds forms between a. Potassium and iodine ion .b.Sodium and sulphide ions . c. Aluminums and chloride ions 2. Why does milk sour when kept for a long time/ 3. What happen when hydrogen combine with oxygen in presence of electric current/ 4. Define electrolysis. 5. What is decomposition reaction? Give an
Premium Hydrogen Iron Nitrogen
LAB 1: Cheesemaking with Enzymes 9E Chihiro Okada Introduction 1. Enzymes - are biological catalyst. 2. Enzymes - are proteins that catalyze chemical reactions. Emporase – an enzymes that speeds up the production of cheese. 3. First milk is pasteurized by heating it to 72℃ for 15 seconds to kill any harmful bacteria. Then‚ the milk is cooled and either a special blend of bacteria or an acidic solution - such as vinegar or lemon juice - is added. The milk is
Premium Milk Cheese Whey
cameras and modified webcams (excellent examples of which can be seen at Damian Peach’s website and on the ESA site). Although modern technology has allowed much detail to be resolved and captured electronically‚ many observers prefer to record their observations of the planet with more traditional sketches and drawings made at the eyepiece‚ a time-consuming but rewarding experience (see for example a selection of sketches produced by observers at the Astronomy Sketch of the Day website). Apart from slight
Premium
_________________. These synapses are always (excitatory or inhibitory). Advantages of the electrical synapses: 1. _______ signal conduction 2. _____________ activity for a group of neurons. 6. The chemical synapse: Chemical
Premium Neuron Action potential Nervous system
research completed using Naturalistic Observation based on the attentiveness of children. Any correspondence should be addressed to Pollyanna.craig@yahoo.com Dr. Lashley PSYCH 209 Section: 0956 Abstract Naturalistic Observation refers to collections of data without manipulation of the environment. The mean goal of naturalistic observation in Psychology is to study the behavior of an organism or human in natural settings. In psychology‚ naturalistic observation has been used in many different
Premium Birth order Developmental psychology Sibling
Environmental Observations I was able to attend an Alcoholics Anonymous meeting at Calvary Lutheran Parish House in Dover‚ PA on a Sunday afternoon. The location was easy to find and close to my house. When I arrived‚ I noticed a group of people smoking near the building and walked over to them and inquired about if I had the right location of the meeting. A gentleman told me to go down the stairs and then I would be in the room that the meeting took place. I walked over to the steps and had to
Premium Peer-to-peer Observation Alcoholism
chemically convert the substance into nutrients. It usually involves mechanical manipulation and chemical action. Mechanical Digestion What is it? This type of digestion involves the mixing‚ grinding or crushing of large pieces of food into smaller places. Why does it take place? So that the food we consume is broken down into smaller pieces before we swallow it which in turn makes process of chemical digestion that takes place later on more effective because it works more efficiently on
Premium Digestion
AND RECOVERY FROM CHEMICAL ADDICTION The Causes & Recovery From Chemical Addiction Dozier‚ Tommy O Argosy University/Atlanta The Causes & Recovery From Chemical Addiction 2 Chemical addiction is the least researched in the medical field. The problem is that chemical addiction is a growing epidemic in urban cities. Chemical addiction has many names‚ but everyone agrees that it is an enormous problem. Chemical addiction can be
Premium Drug addiction Addiction Substance abuse