Komal Patel
Chemistry Honors
Period: 5
February 29, 2016
Chemical Reaction Lab Report
Introduction
A chemical reaction is when substances (reactants) change into other substances (products). The five general types of chemical reactions are synthesis (also known as direct combination), decomposition, single replacement (also known as single displacement), double replacement (also known as double displacement), and combustion. In this lab, the five general types of chemical reactions were conducted and observations were taken before, during, and after the reaction. Then the reactants and observations were used to determine the products to form a balanced chemical equation. The purpose of this lab was to learn and answer the question: How can observations be used to determine the identity of substances produced in a chemical reaction?
Results
Chemical Reactions Conducted in the Lab (#1)
Station:
Type of Reaction:
Balanced Chemical Equation:
1
Synthesis Mg
2Mg(s) + O2(g) MgO(aq)
1
Synthesis Mg and water
MgO(aq) + H2O(l) Mg(OH)2(aq)
2
Decomposition
NaHCO3
2NaHCO3(s) CO2(g) + H2O(l) + NaCO3(s)
3
Decomposition H2O2
2H202(aq) 2H2O(l) + O2(g)
4
Single Replacement
Cu
2AgNO3(aq) + 2Cu(s) 2Ag(s) + Cu(NO3)2(aq)
5
Single Replacement
Zn
Zn(s) + 2HCl(aq) H2(g) + ZnCl2(aq)
6
Double
Replacement
Na2CO3
Na2CO3(aq) + Ca(NO3)2(aq) CaCO3(s) + 2NaNO3(aq)
6
Double
Replacement
NaOH
2NaOH(aq) + CuSO4(aq) Cu(OH)2(s) + Na2SO4(aq)
Combustion
Methane Gas
CH4(g) + 2O2(g) CO2(g) +
- Results: When a lighted match was held 2cm away from the unlighted candle in its smoke, the flame would jump from the match to the wick having been carried by the smoke.
The purpose of doing this lab was to apply the knowledge of chemical reactions to identify an unknown substance. Research was done prior to doing the experiment to provide a basic understanding of the chemical reactions occurring. There are two elementary aspects a chemical solution. First, there’s the reactant. The reactant is the substance added that reacts with another chemical, after the chemical reaction has run its course, what is left is called the product. There are about seven ways to tell if a chemical reaction has taken place; a few of which include color change, precipitate, the formation of gas, and temperature change. In this particular experiment, the question that was being investigated was: What is the unidentified chemical substance? The hypotheses made was: The unnamed chemical is Calcium Chloride considering each are clear liquids.
Procedure- The procedure for this lab includes many simple steps and a few different things we are testing. Our first Procedure was to combine water and salt to see what kind of reaction it would make. First we fill the graduated cylinder with 100 ml of water. We then measured 1.0 grams of table salt on a balance to get an accurate amount. After, we took the measured amount of salt and poured it into the water filled beaker. Lastly, we watched and recorded the reaction.
There are now many classification systems to classify the different types of reactions. These include decomposition, polymerization, chain reactions, substitute reactions, elimination reactions, addition reactions, ionic reactions, and oxidation-reduction reactions.
Purpose: The purpose of this experiment is to observe a variety of chemical reactions and to identify patterns in the conversion of reactants into products.
The purpose of this lab was to experimentally and scientifically ascertain the percentage of oxygen in Chem B at Woonsocket High School. It was hypothesized that if the percentage of oxygen is measured experimentally in Chem B at Woonsocket High School, then it would be higher than the percentage of oxygen in dry air, which is 20.95%, because the air is not dry due to moisture in the air from people breathing and the altitude of where the experiment takes place may affect it as well.
Add a magnet to the bottom of the paper and observe what happens. In experiment 2 fill a small beaker until it is half-empty with cold water. Obtain the test tube in the warm water and pour it into the cold water. In experiment 3 place a piece of magnesium in a test tube and add 10 drops of hydrochloric acid. Feel the bottom of the tube. In experiment 4 scoop a small amount of sodium bicarbonate to a test tube. Add 10 drops of 6M HCI. Feel the bottom of the tube. In experiment 5 combine 5 drops of barium chloride and 5 drops of sodium sulfate. In experiment 6 mix some sodium chloride in a test tube with 2 mL of
At station A when zinc and hydrochloric acid react with each other it is a chemical change because it creates gas bubbles and temperature change. At station B where NaOH solution and phenolphthalein react with each other it is a chemical change because it changed to the colour purple and the change looked difficult to reverse. Station C in which sulfuric acid and magnesium were to react with each other is a chemical change because it formed gas bubbles and changed colour. Station D where hydrochloric acid and Bromothymol blue were the materials is a chemical change because it changed to the colour yellow and looked difficult to reverse. In Station E where NaCl solution and AgNO3 solution were the materials is a chemical change because the reaction
: During each reaction, something happened. During reaction 1, after adding the nitric acid a red-brown gas was created. The copper first turned green after a few minutes turned into a blue solution. Reaction 2, When acid was added a blue precipitate formed. Reaction 3, when heated the solution turned into a black precipitate.
The purpose of the lab is to study the effect of a chemical reaction, on the change in mass.
In the chemical and physical change lab, we figured out what a chemical change is. A chemical change is a change in which one or more substances are converted into a different substances. That means if a chemical change occurred the substances will be turned into a different substance. In order to know if a chemical change happened you will see bubbles, a color change, energy released as heat and light or a solid participate. The first example, of a chemical change in this lab is bubbles. In stations 6 and 8 each had bubbles in them. In station 6 the zinc was put into the HCI acid and once they touched they got bubbly and cloudy. Also in station 8 when a spoonful of baking soda and HCI acid touches the solution, it started to bubble and fizz.
Introduction Chemical reactions are affected by the acidity of the solution in which they occur. pH can determine whether or not the reaction occurs, and whether it occurs at an appropriate rate, and must thus be controlled. Biochemical reactions are especially sensitive to pH. Molecules contain a group of atoms that may be charged or neutral. Whether or not the molecule is charged depends on the pH, and has an affect on the biological activity of a cell. What is the standard pH inside a cell?
A chemical reaction is a process in which elements or compounds react with one another to create new or different substances. There are two parts to a reaction. Those two parts are the products and the reactants. The reactants are the chemicals or chemical compounds that are going through the reaction itself. The products are chemical elements or chemical compounds that are produced as a result of the reactant or reactants reacting. There are four key indications that there’s a chemical reaction is taking place. Those four signs include a change in color and/or odor, formation of a precipitate or a gas, the release or absorption of energy (light, heat, electricity), and if the reaction is irreversible. Along with this information, there are ways to predict the products of a reaction.
A chemical reaction is usually accompanied by easily observed physical effects, such as the emission of heat and light, the formation of a precipitate, the evolution of gas, or a color change. Absolute confirmation of a chemical change can only be validated by chemical analysis of the products. There are many different types of chemical reactions. Scientist have classified the many different reactions into categories. The five major categories are combination or synthesis reaction, decomposition reaction, displacement or replacement reaction, acid base reactions, and combustion
The Observing Chemical Reactions lab called for us to determine from a list of possible chemical formulas which chemical reaction is the most green to run. From here we concluded from a list of chemical reactions as to which chemicals are the least hazardous to people and the environment. After choosing which experiments to work on as a group we then conducted the experiments individually. The reactions that we decided to pursue were A1, B2, C1, D1, E1 and F2. After concluding which reactions should be tested we came together once more to discuss a central research question.