Lab Report #1 Chemistry is Li Fe PDF

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Name: Nguyen Nguyen Date: 02-08-2021 TA/Professor Name: Qize Zhang Experiment 1: What is around us? “Chemistry is LiFe.”

Introduction Chemistry exists all around us and it is important for us to understand how it affects our lives. Around us, chemicals are found all over.

For example, chemicals are used in cooking

ingredients, medications, cleaners, and many other things that can be commonly found in every household. As such, having a great knowledge of chemistry will aid you in making crucial choices to better your life, others’ lives, and even the environment. In this experiment, we will be able to practice nomenclature by writing and naming different compounds from selected elements.

Materials ● The Periodic Table - to select the 8 elements for the experiment. ● The Computer - to research about the selected elements as well as how it interacts with other elements. ● Pen and Paper - to list out all 50 compounds (25 ionic compounds and 25 molecular compounds). ● Lab Manual - to use the other provided materials (the Naming Compounds Chart and the procedures).

Observations and Experimental Metals

Nonmetals

1. Scandium (Sc)

1. Oxygen (O)

2. Titanium (Ti)

2. Fluorine (F)

3. Vanadium (V)

3. Chlorine (Cl)

4. Chromium (Cr)

4. Selenium (Se)

Name of Ionic Compound

Chemical Formula of Ionic Compound

Name of Molecular Compound

Chemical Formula of Molecular Compound

Chromium (II) Oxide

CrO

Selenium Dioxide

SeO2

Chromium (III) Oxide

Cr2O3

Selenium Trioxide

SeO3

Chromium (IV) Oxide

CrO2

Selenium Dichloride

SeCl2

Chromium (II) Chloride

CrCl2

Selenium Tetrachloride

SeCl4

Chromium (III) Chloride

CrCl3

Selenium Hexachloride

SeCl6

Chromium (IV) Chloride

CrCl4

Selenium Difluoride

SeF2

Chromium (II) Selenide

CrSe

Selenium Tetrafluoride

SeF4

Chromium (III) Selenide

Cr2Se3

Selenium Hexafluoride

SeF6

Chromium (IV) Selenide

CrSe2

Dichlorine Monoxide

Cl2O

Chromium (II) Fluoride

CrF2

Dichlorine Trioxide

Cl2O3

Chromium (III) Fluoride

CrF3

Dichlorine Pentoxide

Cl2O5

Chromium (IV) Fluoride

CrF4

Dichlorine Heptoxide

Cl2O7

Scandium (III) Fluoride

ScF3

Difluorine Monoxide

F2O

Scandium (III) Oxide

Sc2O3

Difluorine Pentoxide

F2O5

Scandium (III) Chloride

ScCl3

Hydroselenic Acid

H2Se

Scandium (III) Selenide

Sc2Se3

Selenic Acid

H2SeO4

Titanium (II) Oxide

TiO

Selenous Acid

H2SeO3

Titanium (III) Oxide

Ti2O3

Hydrofluoric Acid

HF

Titanium (IV) Oxide

TiO2

Fluoric Acid

HFO2

Titanium (II) Chloride

TiCl2

Fluorous Acid

HFO3

Titanium (III) Chloride

TiCl3

Perfluoric Acid

HFO4

Vanadium (II) Oxide

VO

Hydrochloric Acid

HCl

Vanadium (III) Oxide

V 2O 3

Chloric Acid

HClO2

Vanadium (II) Chloride

VCl2

Chlorous Acid

HClO3

Vanadium (III) Chloride

VCl3

Perchloric Acid

HClO4

Discussion and Conclusion As for this experiment, it is important to properly name the compounds as there are many laws and rules to follow. For example, to name all my ionic compounds, first you need to identify the ion charges of the transitional metal according to its oxidation number. After that, list the name of the transitional metal followed by the roman numeral that indicates the ion charges. As for the negative ion in the ionic compounds, if it is monatomic, add the ending -ide to the negative ion. If it is polyatomic, add the -ate, -ite (if it had one less O than -ate), per___ate (if it had one more O than -ate), and hypo___ite (if it had one less O than -ite). As for naming the molecular compounds, there is one thing you need to know before anything - is it an acid? This is indicated by whether the molecular compound starts with a Hydrogen or not. For acid, if H is combined with just an anion atom that is not an oxygen, it follows the rule of “hydro___ic acid” as the blank will be filled with the name of the ion that is attached to H. However, if the ion is a polyatomic ion that consists of oxygen, it follows another rule. If the ion name ended in -ate,

the acid name will be ___-ic acid. If the ion name ended in -ite (one less O than -ate), the acid name will be ___-ous acid. If the ion has the prefix of per- or hypo-, the prefix stays the same and the ending follows the previously mentioned rule. As for the non-acid, there are two main rules to follow. One, use the name of the first atom with prefixes (that indicate the number of moles of that element in the molecular formula such as mono-, di-, tri-, etc.) except for mono-. Two, add the ending -ide to the second atom and attach the appropriate prefix according to the number of moles of the element in the molecular formula.

Focus Questions

1. What types of compounds do you know? Ionic compounds - consists of positively charged cations, typically metals, and negatively charged anions, typically nonmetal - and molecular compounds - a compound that consists of a combination of non-metals, and acids. 2. When naming different types of compounds do you need to follow different rules? Explain using examples. Yes, when naming compounds, you must follow specific rules for ionic compounds and molecular compounds. For ionic compounds, it is important to note that the cations and anions typically combine to form. To achieve this, the ratio of cations to anions must equate the molecule with a neutral charge. When naming an ionic compound, the leading cation retains the same name as the element it is representative of. For the concluding anion, you must replace the ending with “-ide”. For example, CaO, would be referred to as calcium oxide. However, if the metal has multiple oxidation numbers, or multiple charges in ions, you must indicate the specific

charge by the roman numeral in the parentheses. For example, CrO would be written as chromium (II) oxide and Cr 2O3 would be written as chromium (III) oxide. However, if it is polyatomic, add the -ate, -ite (if it had one less O than -ate), per___ate (if it had one more O than -ate), and hypo___ite (if it had one less O than -ite). When it comes to simple molecular compounds, the more electrically positive atom is typically written first, followed by the more electronegative atom accompanied by the “-ide” suffix. Furthermore, prefixes are used to represent the given number of atoms of an element in the compound. For example, SeF6 would be called selenium hexafluoride. As for acid, if H is combined with just an anion atom that is not an oxygen, it follows the rule of “hydro___ic acid” as the blank will be filled with the name of the ion that is attached to H. For example, if HCl is hydrochloric acid. However, if the ion is a polyatomic ion that consists of oxygen, it follows another rule. If the ion name ends in -ate, the acid name will be ___-ic acid - such as H 2SeO4 is selenic acid. If the ion name ends in -ite (one less O than -ate), the acid name will be ___-ous acid - such as H2SeO3 which is selenous acid. If the ion has the prefix of per- or hypo-, the prefix stays the same and the ending follows the previously mentioned rule- such as HClO 4 which is Perchloric acid. 3. Does it matter in which order you combine your elements when writing chemical formulas for ionic compounds? Yes, the order in which you combine elements when writing chemical formulas for ionic compounds does matter. Typically, when writing ionic compounds, the positive cation is listed first, followed by the negative anion. 4. Which laws govern the formation of compounds?

When forming compounds, there are three laws: The Law of Conservation of Mass, the Law of Definite Proportions, and the Law of Multiple Proportions. The Law of Conservation of Mass stated that “in a chemical reaction, the total mass of the products equals the total mass of the reactants.” This means that the product must consist of the same amount of each atom as the reactants, nothing is added nor lost. The Law of Definite Proportions stated that “no matter how a given chemical compound is prepared, it always contains the same elements in the same proportions by mass.” For example, all samples of the compound carbon monoxide contain 42.88 % carbon and 57.12 % oxygen by mass. The Law of Multiple Proportions stated that “if two elements combine to form more than one compound, the masses of one element combining with a fixed mass of the other are in a simple ratio to one another.” For example, CO and CO 2 consist of the same elements but different ratios of oxygen. In CO, 1 gram of C worth 1.33 grams of O, but in CO 2, 1 gram of C worth 2.667 grams of O. This is reflected upon the chemical formula itself as in CO, 1 mole of C equates to 1 mol of O while in CO 2, 1 mol of C equate to 2 mol of O, double just like the ratio of its masses.

Post-Lab Assessment Questions 1. For the following pairs of ions, write the formula of the compound that you would expect them to be form: a. Magnesium and cyanide: Mg(CN)2 b. Chromium (III) and oxygen: Cr2O3 c. Cobalt (III) and sulfite: Co2S3 2. Platinum is a transition metal and forms two different ions, Pt 2+ and Pt4+. Write the formulas for the compounds for each platinum ion with:

a. Fluorine ions: PtF2 and PtF4 b. Hydroxide ions: Pt(OH)2 and Pt(OH)4 c. Chromate ions: PtCrO4 and Pt(CrO4)2 3. Name the following compounds a. SO3: Sulfur Trioxide b. GaCl3: Gallium (III) Chloride c. Li3PO4: Lithium Phosphate d. TiO2: Titanium (IV) Oxide 4. Write the formulas for the following compounds. a. Sulfur pentachloride: SCl5 b. Nitrogen dioxide: NO2 c. Zinc (II) nitrate: Zn(NO3)2 d. Barium sulfide: BaS

References Boundless.

(n.d.).

Boundless

chemistry.

Retrieved

February

08,

2021,

from

https://courses.lumenlearning.com/boundless-chemistry/chapter/namingcompounds/#:~:text=When%20naming%20molecular%20compounds%20prefixes,and %20%E2%80%9Cdeca%E2%80%9D%20is%20ten. Libretexts. (2020, August 15). Law of multiple proportions. Retrieved February 08, 2021, from https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_

Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Atomic_Theory/Dal ton's_Atomic_Theory/Law_of_Multiple_Proportions...