# Chemistry

# 📏 SI Prefixes & Metric System Conversion 📏

This

**study guide**outlines the**20****SI**(**International System of Units)**prefixes used to form decimal multiples and submultiples.

This

**video**presents a mnemonic device to remember the**12 International System of Units (SI) prefixes**:**T**era,**G**iga,**M**ega,**k**ilo,**h**ecto,**d**ec**a**,**d**eci,**c**enti,**m**ili,**m**icro (**μ)**,**n**ano and**p**ico:**T**he**G**reat**M**an**k**ing**h**enry’s**da**ughter Betsy**d**rinks**c**old**m**ilk**μ**ntil**n**ine**p**m.

This

**video**explains how to**convert**between**metric units of measure**using a**visual aid**: "**The Metric Staircase**."This

**Biology**lesson, written by**Ilysse Baum**shows how the "**Metric Staircase**" can also be applied to the conversion of ocular micrometers.

This

**video**provides a comprehensive overview of how to convert**metric quantities**using the**base unit**,**liter**, and the**SI prefixes****milli**-,**centi**-,**deci**-,**deca**-,**hecto-**, and**kilo-.**

# 🌡 Temperature Scales & Density 🌡

This

**video**compares the**Celsius**and**Fahrenheit**temperature scales, and explains that the**boiling point**of water is 212°**Fahrenheit**and 100°**Celsius,**and the**freezing point**of water is 32°**Fahrenheit**and 0°**Celsius**.

This

**video**explains how to convert**temperatures**in degrees**Fahrenheit**to temperatures in degrees**Celsius**.

This reference guide shows how to convert

**Celsius and Fahrenheit****temperatures**.

This

**video**outlines the following conversions:**Fahrenheit to Celsius and vice versa**, and**Celsius to Kelvin and vice versa**. It also covers the**temperature at which Celsius equals Fahrenheit**, and**absolute zero**.

This

**video**compares the boiling and freezing points on the**Fahrenheit**,**Celsius**, and**Kelvin**scales. It also describes how to**convert**between these temperature scales.

This

**video**defines**boiling point elevation**as the raising of a solvent's boiling point due to the addition of a solute, and**freezing point depression**as the lowering of a solvent's freezing point due to the addition of a solute. As the**boiling point of a solvent increases**, its**freezing point decreases**.

This

**video**provides**examples**and**practice problems**on**boiling point elevation**and**freezing point depression**. In addition, this video also shows how to**determine which solution**will have the**highest boiling point**.

This

**study guide**highlights the**difference**between**mass and weight**, and provides**fields**to**input mass and weight on various planets**.

This

**video**explains how**temperature**is different than**heat**, and uses an example to explain why**substances with the same temperature can feel hotter or cooler than each other**.

This

**study guide**explores the**difference**between**temperature and heat**, and defines the**heat equation**.

This

**video**explains the difference between**intensive properties**and**extensive properties. Intensive properties**do not depend on the quantity of matter (i.e.**density**).**Extensive properties**do depend on sample size (i.e.**volume**,**mass**, etc.).

This

**study guide**defines and provides examples of**intensive**and**extensive**properties.

This

**video**provides an**explanation**of the**definition of density**(**density = mass/volume**) using a**visual aid**: a**density triangle**.

This

**video**provides an**explanation**of what**density**is, and includes three**examples**for**calculating density**,**mass,**and**volume**.

This

**study guide**provides an introduction to**density**,**determining density**, c**alculating specific gravity**, and the**uses of density in the geosciences**.

# 🔸 Subatomic Particles 🔸

This

**video**defines the charges of the three subatomic particles:**proton****(p)**:**+1**,**neutron (n)**:**0**, and**electron (e-)**:**-1**. It also explains that**protons**and**neutrons**are**heavier**than**electrons**and reside in the**nucleus, at the center of the****atom**.**Electrons**are relatively lightweight and exist in a**cloud orbiting the nucleus**.

This

**study guide**defines the three main subatomic particles:**protons**,**electrons**, and**neutrons**. It also describes the**locations**,**charges**, and**masses**of**protons**,**neutrons**, and**electrons**, and describes how to**determine the number of protons and electrons in an atom**.

This

**study guide**provides a comprehensive**overview**of the following topics: Introduction: Structure of Atom, Atomic Number, Bohr’s Model of Atom, Isobars, Isotopes, Mass Number, Neutrons, Rutherford’s Model of an Atom, Thomson’s Model of an Atom, Valency, How are Electrons Distributed in Different Orbits (Shells)?, Sub-Atomic Particles, Atomic Models, Shapes of Atomic Orbitals, Energies of Orbitals, Quantum Numbers, Development Leading to Bohr’s Model of Atom, Emission and Absorption Spectra, Towards Quantum Mechanical Model of Atom.

This

**video**shows how to read the**periodic table of elements**. It defines the**atomic number**as the**number of protons in the nucleus of an atom**. It defines**atomic mass**as the**mass of an atom**of a chemical element expressed in**atomic mass units**. It is approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes.

This

**video**explains how to calculate the number of**protons**,**neutrons**, and**electrons**in an**atom**or in an**ion**. It also explains the difference between**atomic number**,**mass number**, and the**average atomic mass**for the isotopes of the elements in the**periodic table**.

This

**video**explains the process of naming**covalent molecular compounds**with**prefixes**.

This

**video**illustrates the difference between**structural**and**bond line formulas**, and provides**visualization**s of both formulae.

This

**video**teaches how to**draw bond line structures**,**representations of molecular****structure**in which**covalent bonds**are represented with**one line**for**each level**of**bond****order**.

This

**study guide**classifies the following**separation techniques**as follows:**Filtration/Dialysis**for**Size**:**Exclusion Chromatography for Particle Size**,**Centrifugation**for**Mass or Density**,**Masking**for**Complex Formation**,**Distillation/Sublimation/Recrystallization**for**Change in Physical State**,**Precipitation/Electrodeposition/Volatilization**for**Change in Chemical State**, and**Extraction/Chromatography**for**Partitioning Between Phases**.

# ✰ Avogadro's Number, The Mole & Molar Mass ✰

This

**video**explains the concept of**moles**and how it relates to**mass in grams**by the**molar mass**of a compound. It also explains how**moles relate to atoms****and molecules**through**Avogadro's number**.

This

**video**conceptualizes the**definition**of a**mole**of a substance as being equal to**6.022 × 10²³ units**of that substance (such as**atoms, molecules, or ions**). The number**6.022 × 10²³**is known as**Avogadro's number**.

This

**study guide**explains the concept of a**mole**, and provides**examples**of**calculating the molar mass**of:**Al(NO**_{3}**)**_{3}_{, }**Ba(SCN)**_{2}_{, }**CO**,**N**_{2}_{, }**Ar**,**HCl**,**CaSO**_{4}**⋅**^{1}**⁄**_{2}**H**_{2}**O**,**Ca(C**_{2}**H**_{3}**O**_{2}**)**_{2}_{, }**(HOOCCH**_{2}**)**_{2}**NCH**_{2}**CH**_{2}**N(CH**_{2}**COOH)**_{2, }and**nitrogen**.

This

**video**focuses on**Avogadro's number**and how it is used to convert**moles to atoms**. This video also explains how to calculate the**molar mass of a compound**, and how to**convert from grams to moles**.

This

**video**explains how to calculate the**molar mass****of a compound**, and provides various**examples**to find the**molar mass**of chemical compounds.

This

**video**explains how to calculate the**molar mass****of a compound,**which is helpful especially in**mole to gram conversions**, in**three easy steps**.

# ☍ Percent Composition ☍

This

**video**explains how to find the**composition by mass**of each element in a compound. The**molar mass**of the entire compound must be found in order to**calculate the mass percent of each element in the compound**.

This

**video**uses an example to calculate the**mass percent****of an element in a compound**by**dividing the mass of the element**in**1 mole of the compound**by the**compound's molar mass****and multiply the result by 100**.

This

**video**shows how to calculate the**mass percent****of an element in a compound**by**dividing the mass of the element**in**1 mole of the compound**by the**compound's molar mass****and multiply the result by 100**. The example provided shows how to calculate the**mass percentages**of the elements**Carbon (C)**,**Hydrogen (H)**, and**Oxygen (O)**in**Glucose (C6H12O6)**after**Calculating the Molecular Mass of Glucose**.

This comprehensive

**study guide**provides**explanations**and**examples**of the following concepts:**percent composition**,**determining percent composition from formula mass**,**determining empirical formulas**, and**deriving empirical formulas from percent composition**.

This

**study guide**explains how to calculate the**mass ratio**of**sulfuric acid**using the following four steps: (1)**Determine the molar mass of each element present**, (2)**Determine the mass of each individual element present**, (3)**Determine the molar mass of the compound**, and (4)**Divide the mass of each element present by the molar mass**.

This

**video**shows how to calculate the**theoretical**and**percent yield**. The**theoretical yield**is the**maximum amount of product that can be produced in a reaction**. The**percent yield**is equal to the**actual yield divided by the theoretical yield times 100%.**

This

**video**explains how to calculate the**percent yield**,**actual yield**, and**theoretical yield**of a product produced in a chemical reaction given the**mass in grams of the reactants**. It also includes**stoichiometry**practice problems with**limiting reagents**and**excess reactants**.

# ✦ Stoichiometry & Conversion Factors ✦

This

**video**provides an**overview**to**stoichiometry**, the branch of chemistry which**expresses the quantitative relationship between reactants and products in a chemical equation**.

This

**study guide**covers various topics in stoichometry including:**stoichiometric coefficients**,**variation in stoichiometric equations**,**density**,**percent mass**,**molarity**,**empirical formulas**, and**molecular formulas**.

## ✦ Mole Conversions 📺

This

**video**explains**mole to mole conversions**,**grams to grams**and**mole to gram dimensional analysis**problems. It also contains**mole ratio**practice problems. The**molar ratio**can be found using the**coefficients of the balanced chemical equation**. The conversion from**moles to grams and grams to moles**can be accomplished using the**molar mass of the substance**.

This

**video**focuses on converting units of measurement with**conversion factors**. It explains how to convert**units of length**,**time**,**capacity**,**volume**,**area**,**mass**,**speed/velocity**, and**density**.

# 🔹 Scientific Notation & Significant Figures🔹

This

**video**discusses how**scientific notation**is used to express**numbers that are too large or too small to be compactly written in decimal form**. It also explains how to express**Avogadro's number**in**scientific notation**.

This

**video**provides various**numerical examples**to express both large and small quantities in**scientific notation**.

This

**study guide**outlines how to**convert**quantities written in**scientific notation to standard form**, and from**standard form to scientific notation**. It also provides examples of**calculations**and**approximations**with scientific notation, and explains**significant figures**.

This

**video**explains the**seven basic units**in the**SI system**: the**meter****(m)**, the**kilogram****(kg)**, the**second****(s)**, the**kelvin (K)**, the**ampere (A)**, the**mole****(mol)**, and the**candela (cd)**. It also explains how to determine using the following**five rules**: (1)**All non-zero numbers are significant**, (2)**Zeros between two non-zero digits are significant**, (3)**Leading zeros are not significant**, (4)**Trailing zeros to the right of the decimal are significant**, (5)**Trailing zeros in a whole number with the decimal shown are significant**.

# ⚛︎ Chemical Formulas & Balancing Chemical Equations ⚛︎

This

**video**explains how to**balance a chemical reaction**: the**same number of atoms of each element**must be on**both sides of the equation**.

This

**video**tutorial defines**five simple steps**to use when**balancing chemical equations**.

This

**video**provides**tips**on how to**balance more complicated chemical reactions**. It also provides an**example**of**balancing**the**combustion reaction**of ethylene,**C₂H₄**.

This

**video**uses different colors to relate a**balanced chemical equation**to the**structural formulas**of the**reactants and products**.

This

**video**highlights the differences between**empirical**,**molecular**, and**structural**chemical formulas.**Empirical formulas**show the simplest**whole-number ratio of atoms in a compound**.**Molecular formulas**show the**number of each type of atom in a molecule**.**Structural formulas**show the**arrangement of the molecule**.

This

**video**defines**oxidation and reduction**using an example:**NaCl**. Oxidation is the**gain**of oxygen. Reduction is the**loss**of oxygen.

These

**videos**explain how to**balance redox reactions**under**acidic conditions.**They also help to**identify which half reaction is oxidation and reduction**.

These

**videos**explain how to**balance redox reactions**in**basic solutions**using the following steps: (1)**separate the net reaction into two separate half reactions (oxidation and reduction)**, (2)**balance the atoms first under acidic conditions using H+ and H2O,**and (3)**balance the charges by adding electrons to the side of the chemical equation with the highest oxidation state**. Once the**electrons in both half-reactions are equal, the two reactions may be combined together to form the net reaction**. To**neutralize the acid, OH- ions are added to both sides of the equation**.

## 🔵 Química, Chemistry Khan Academy Videos en Español 📺

This link provides comprehensive

**video**tutorials from the**Khan Academy en Español**in such topics in**Chemistry**as**:**Atoms, Ions and Compounds, Chemical Reactions and Stoichiometry, Electronic Structure of Atoms, Periodic Table, Chemical Links, Gases and Molecular Kinetic Theory, States of Matter and Intermolecular Forces, Chemical Balance, Acids and Bases, Buffer Solutions, Titrations and Solubility Balance, Thermodynamics, Redox and Electrochemical Reactions, Kinetics, Nuclear Chemistry, and Alkanes, Cycloalkanes and Functional Groups.