Verna Wang Hannah Palmer CHEM 101-069 Lab 11-19-16 Stoichiometry and Limiting Reagents Lab Report Purpose: We are using the reaction of sodium hydroxide and calcium chloride to illustrate stoichiometry by demonstrating proportions needed to cause a reaction to take place. Background: Just like a recipe would call for a specific amount of one ingredient to a specific amount of another, stoichiometry is the same exact method for calculating moles in a chemical reaction. Sometimes, we may not have enough of or too much of one ingredient , which would be defined as limiting and excess reagent, respectively. Ideally, every mole of each reagent would be used up, and theoretical yield, we are assuming that every last mole of the reactants would
1. For the demo experiment, the balanced chemical equation is as follows: (NH4)2Cr2O7(s)=Cr2O3(s)+N2(g)+4H2O(g). After the lightning of Ammonium dichromate, Chromium (III) oxide was formed while the Nitrogen and Water escaped into the atmosphere in a gaseous phase. Ammonium dichromate((NH4)2Cr2O7) gave rise to Chromium (III) oxide (Cr2O3), Nitrogen Gas(N2) and water (H2O) In terms of microscopic level, the ratio between reactants and products is as follows. One mole of Ammonium dichromate will give rise to one mole of 1 mole of Chromium (III) oxide and 1 mole of Nitrogen gas and 4 moles of Water is gaseous phase.
With the perfect conditions water boils at “212°F: Full rolling boil.”(Lopez,K) Another factor in boiling point is any impurities residing the the water itself. “For instance, if water comes to a boil at exactly 100 degrees Celsius at 1 atmosphere, it means that is pure and does not contain any impurities. If the boiling point differs, it must mean that the water is impure.”(Factors that affect the boiling point of water.) Overall there are many ways that water 's boiling point can be affected by outside forces, but the focus will be on alkaseltzer tablets and how they influence water 's boiling point. The active ingredients in the alka seltzer tablet are “As the tablets dissolve, the sodium bicarbonate splits apart to form sodium and bicarbonate ions.
To understand this lab completely, it is important to know the concepts limiting and excess reactant. A limiting reactant is the reactant that limits the amount of product that can be produced in a reaction. An excess reactant is the opposite, or the reactant that remains after a chemical reaction is performed and the limiting reactant runs out (Stoichiometry: Limiting). The stoichiometry calculations determining what should happen can be found in the calculations section. The solid should form calcium carbonate.
Explain what is meant by relative atomic mass?- Relative atomic mass is the measure of the mass of an element which consists of the protons and neutrons; it is always the bigger number and has the symbol Ar. An obvious example of this is oxygen has the Ar of 16 yet sodium has the Ar of 23. Explain how relative formula mass is calculated using the periodic table- You need to find the relative atomic mass (M) for each atom but this can only be done when the relative atomic mass have been found, then you add all of the masses in the compound together to find the RFM. Sodium Hydroxide is the example we used within our experiment. Na= 23 O= 16 H= 1 NaOH 23 + 16 + 1 = 40 NaOH Mr= 40 Explain how it is possible to work out amounts of substance
Instead of using a simple benzene derivative as a reactant, the substrate being used is ferrocene, which consists of a central iron atom bounded or sandwiched between two cyclopentadienyl rings. This synthesis also involves greener reagents. As stated above, aluminum chloride is often used as a strong Lewis acid catalyst to start the reaction. However, it is corrosive and can give off considerable quantities of acidic and toxic wastes. Since ferrocene is highly reactive (due to its two cyclopentadienyl rings), AlCl3 can be replaced with a more benign catalyst, phosphoric acid.
Introduction:- In organic chemistry the substitution reactions is the most important reactions, especially Nucleophilic aromatic substitution reactions where nucleophile attacks positive charge or partially positive charge As it does so, it replaces a weaker nucleophile which then becomes a leaving group. The remaining positive or partially positive atom becomes an electrophile. The general form of the reaction is: Nuc: + R-LG → R-Nuc + LG: The electron pair (:) from the nucleophile (Nuc :) attacks the substrate (R-LG) forming a new covalent bond Nuc-R-LG. The prior state of charge is restored when the leaving group (LG) departs with an electron pair. The principal product in this case is R-Nuc.
The most accurate way to determine RQ is through the bicarbonate buffer reaction where the amount of hydrogen ions show metabolism. Although both RQ and RER measure the exchange rate of O2 and CO2, the two are different because RQ is measured at the cellular level in the tissues, while
Not just the template explanations but actual instructor approved write ups of the assignment. Preferably selected from former students who showed exemplar understanding of content so that learners can have examples on their current level to help with the assignments. Discussions Discussions may need to be altered to incorporate the new information being provided. Not so much how you would use the information provided, but why and would it fit into your particular project. The discussion summary may also contain reminders of the examples and expectations from the assignments which is something easily
This Writing and Rhetoric I course has transformed my writing style greatly. Through this course I’ve learned to analyze and synthesize my ideas in a better way. At first, I was quite reluctant about my writing and would often think that I was not doing a good job. However, Professor Karl and this course have lead me to the right steps that I need to follow in order to become a better writer. Subsequently, the first essay I had to write about was using Mark Edmundson’s Pay Attention!
The law of conservation of mass states that the matter is not created or destroyed in a chemical reaction B. What is Molecule 1. Molecule is an entity consisting of a defined number of atoms covalently bonded together C: Covalent Polar and Nonpolar Bonding 1. Electronegativity power to attract electrons to itself 2. Polarity shared electrons get pull away difference in electrical charge at one end as opposed to the other end 2.3 The Ionic Bond 1.
A net ionic equation shows only the species that actually take part in the reaction. In solution, Na2S dissociates into Na and S2 ions and ZnCl2 dissociates into Zn2 and Cl ions. As per our lab, zinc ions (Zn 2) and sulfide ions (S2) formed an insoluble compound, zinc sulfide (ZnS), while the other product, NaCl, was soluble and remains in solution. This reaction is called a precipitation reaction. The balanced molecular equation is: Na2S(aq) + ZnCl2(aq) = ZnS(s) +2NaCl(aq).
These are also the areas that I will reiterate and emphasize to my students over the course of the unit. I also revised the criteria and the characteristics that differentiate an exceptional paper from an inadequate paper when appropriate. The annotated bibliography rubric is an evaluation tool that I created from scratch but I wanted to maintain the same format as the other rubrics I am utilizing in my
When my group turned the project in, and it was shown to the class my teacher rewrote the assignment according to what we did and used it as an example of great work when recruiting new people. As proud as I was in this project I knew I couldn’t stop there and continued to seek out opportunities to better myself and the environment around me. Some of the favorite things I have done include attending a cyber forensics seminar and obtaining an award in a coding event for best educational game. The reason I choose Embry-Riddle as opposed to
Another category of chemical reactions is single-replacement. In a single-replacement reaction, a molecule composed of a cation, or atom with a positive charge, and an anion, or atom with a negative charge, is introduced to a pure element. When mixed together, the anion from the reactant molecule will transfer over to the pure element, causing the original cation to become a pure element. When magnesium metal is placed in hydrochloric acid: Mg + 2HCl --> MgCl2 + H2. Here, it can be seen that the chlorine anion that was a part of the hydrochloric acid is transferred to the pure magnesium, leaving behind hydrogen.