Chemistry -Grade 10

How is an element’s location on the periodic table related to its Bohr-Rutherford diagram?

Left-right: is how many electrons needed to make a full shell up-down: indicates the number of electron shells an atom has.

What are the major characteristics of metals, non-metals, ionic compounds and molecular compounds

Metals are typically shiny, malleable, and good conductors of heat and electricity.

Non-metals are usually dull, brittle, and poor conductors.

Ionic compounds are compounds made up of a metal and a non-metal.

Molecular compounds, also known as covenant compounds are made up of two or more non-metals that share electrons.

Explain the 5 different periodic table trends based on atomic structure

Atomic Radius

Ionization energy

Electron affinity

Electronegativity

Metallic character

Atomic Radius

• Definition: The distance from the nucleus to the outermost electron.

• Trend:

  • Across a Period (→): Decreases

    • Why: More protons are added to the nucleus (increasing nuclear charge), pulling electrons closer without adding new energy levels.

  • Down a Group (↓): Increases

    • Why: Additional electron shells are added, increasing the size even though nuclear charge also increases.

Ionization energy

• Definition: The energy required to remove an electron from a neutral atom.

• Trend:

  • Across a Period (→): Increases

    • Why: Electrons are held more tightly due to increasing nuclear charge.

  • Down a Group (↓): Decreases

    • Why: Electrons are farther from the nucleus and more shielded, making them easier to remove.

Electron affinity

• Definition: The energy change when an atom gains an electron.

• Trend:

  • Across a Period (→): Generally becomes more negative (increases in magnitude)

    • Why: Atoms more readily accept electrons to fill valence shells.

  • Down a Group (↓): Becomes less negative (decreases)

    • Why: Larger atoms have a weaker attraction for extra electrons due to increased distance and shielding.

Electronegativity

• Definition: An atom’s ability to attract electrons in a chemical bond.

• Trend:

  • Across a Period (→): Increases

    • Why: Atoms have more protons and a stronger pull on bonding electrons.

  • Down a Group (↓): Decreases

    • Why: Increased atomic size reduces the nucleus’s pull on shared electrons.

Ionic vs. Molecular (covenant) naming

Ionic: metal name + non-metal + -ide

Molecular: prefixes + -ide

Lewis Dot diagram

Bohr Rutherford diagram

Diatomic elements

HOFBrINCl

Word equations

Names of the chemicals are written out with arrows and addition signs.

Skeleton equations

Formula of chemicals written, with arrows and addition signs.They do not show the amounts or states of the reactants and products.

Balanced chemical equations

Final step, where the amount of elements on one side is the same as the other, written with formula names.

Law of Conservation of Mass

The mass of one element at the beginning of a reaction must equal the mass of the element at the end of a reaction.

Signs of chemical change

• Change in:

  • Color

  • Temp.

• Production of:

  • Gas

  • Odor

• Formation of a precipitate.

Synthesis

A chemical reaction where two products become one.

A+B = AB

Decomposition

A chemical reaction where one product becomes two.

AB = A+B

Single displacement

A chemical reaction where an element displaces another in a compound.

A + BC = AC + B

Double displacement

A chemical reaction where two compounds exchange components.

AB + CD = AC + BD

Complete combustion

When a reaction starting with methane (ch₄) (or any other fuel) ends ONLY with water and carbon dioxide as products.

CH₄​+2O₂→CO₂​+2H₂O

Incomplete combustion

When a reaction starting with methane (ch₄) (or any other fuel) ends with ANYTHING OTHER than water and carbon dioxide as products.

CH₄​+O₃→CO​+2H₂O

How to use the Activity Series to determine whether single displacement with occur?

The Activity Series is a list of metals arranged in order of decreasing reactivity. To determine if a single displacement reaction will occur, compare the reactivity of the free metal with that of the metal in the compound; if the free metal is more reactive, the reaction will take place.

How to use the solubility table for double replacement?

When looking for double displacement, you have to make sure that ONE of the products are soluble _(aq) and the other is insoluble _(s), only then can you have a reaction. (if both are soluble then no reaction happens)

Catalyst

A substance that increases the rate of a chemical reaction without being consumed in the process. Catalysts work by lowering the activation energy needed for the reaction to occur.

Characteristics of an acid

A substance that has a PH level below 7, and has the ability to turn blue litmus paper red.

Characteristics of a base

A substance that has a PH level of above 7, and has the ability to turn red litmus paper blue.

Naming acids without oxygen (binary acids)

Start with Hydro-, add the non-metal root, and end with -ic acid.

HBr = Hydrobromic acid

Naming acids with oxygen/polyatomic ion (oxyacids)

FORGET ABOUT THE HYDRO- Start with the name of the polyatomic ion, if the poly end with:

-ate, change to -ic

-ite, change to -ous , and add "acid."

Naming bases

Write the name of the cation (+) first, then the anion (-), ALWAYS followed by Hydroxide.

Neutralization reactions

ACID + BASE = WATER + SALT

One of the products always has to H₂O

Neutralization reactions application

• Antacids:

  Antacids neutralize excess stomach acid, relieving indigestion and discomfort. 

• Baking:

  Baking soda (sodium bicarbonate) is a base that reacts with acids in baking powder, creating carbon dioxide gas which makes baked goods rise. 

Ionic vs. covalent reaction

Ionic:

Between a metal and a non-metal

Covalent (molecular):

Between a non-metal and a non-metal

Naming Compounds with polyatomics

Just write the name of the cation followed by the name of the anion.