Chemistry Experiments
Jared Baltzell, Jacob Feltner, Lindsay Creque, Jaclyn Hood
A. Introduction
Reactants: A substance that takes part in and undergoes change during a reaction.
Products: The compounds that are formed when a reaction goes to completion.
Coefficients: A multiplier or factor that measures some property.
b. Secondary Objective: observing evidence of chemical reactions
The following 4 observations let you know that a chemical reaction has occurred:
i. Formation of a precipitate
ii. Formation of a gas
iii. Change in temperature/ emitting light
iv. Change in color
B. Analysis of Reactions
a. We could tell that there was a chemical reaction occurring because there was a change in color and a formation of a gas. The light blue color turned darker and smoke came out of the test tube.
b. The term "hydrate" means a substance that contains water or it's elements.
c. This reaction is decomposition.
Experiment 2: Potassium iodide reacts with lead (II) nitrate to yield...
b. When you write a balanced equation the words "reacts with" means that you will be mixing two things together. In this experiment we had potassium iodide reacting with lead (II) nitrate.
c. This reaction is a double replacement.
d. 2_KI + Pb(NO3)2 --> 2_KNO3 + PbI2
Experiment 3: Magnesium reacts with oxygen gas to form...
b. Since oxygen is a BrINClHOF element, that means it cannot stand as one atom on its own.
c. The type of reaction that occurred in this experiment was synthesis.
d. Balanced equation: 4_Mg + 2_O2 --> 4_MgO
Experiment 4: Zinc metal reacts with hydrochloric acid to produce...
b. Cation- Is a positively charged ion
Anion- Is a negatively charged ion
c. The reaction that happened was a single replacement reaction.
d. The balanced equation is: 2_HCl + Zn --> ZnCl2 + H2
e. The product that was formed is ZnCl2 + H2
Experiment 5: Hydrogen peroxide breaks down to form water and oxygen gas.
b. The manganese dioxide is a catalyst. A catalyst is a substance that speeds up a chemical reaction, but it isn’t consumed by the reaction.
c. This reaction is decomposition.
d. MgO2 (above arrow)
2_H2O2 → 2_H2O + O2
e. When the glowing splint went into the test tube, the flame grew brighter. This is because of the O2.
C. Conclusions
i. dissolving salt in water is chemical.
ii. melting ice is physical.
iii. milk turning sour is chemical.
iv. burning fireworks is chemical.
v. a 2-liter bottle going flat is physical.
vi. frying an egg is chemical.b. Symbol: (s) What it means: ionic compounds that won't dissolve at all or will only slightly dissolve are called insoluble which is what (s) stands for. Experiment #1 Chemical used: Copper (II) sulfate pentahydrate crystals
Symbol: (l) What it means: liquid
Symbol: (g) What it means: gas Experiment #4 Chemical used: hydrochloric acid
Symbol: (aq) What it means: soluble Experiment #2 Chemical used: potassium iodide and lead (II) nitrate