Flashcards: Periodic Table and Bonding Fundamentals — 24 cartões

Periodic table — structure?

Organized by atomic number in periods and groups.

Period — definition?

Horizontal row with increasing atomic number.

Group — definition?

Vertical column with similar properties.

Atomic number — role?

Number of protons, identifies element.

Electron shells pattern — rule?

Fill 2, 8, 8… electrons per shell.

Valence electrons — location?

In the outermost shell.

Metals — properties?

Shiny, malleable, good conductors.

Non-metals — properties?

Dull, brittle, poor conductors.

Reactivity trend — alkali metals?

More reactive down the group.

Reactivity trend — halogens?

More reactive up the group.

Ion — definition?

Charged atom or molecule.

Cation — charge?

Positive ion.

Anion — charge?

Negative ion.

Ion formation — metals?

Lose electrons, form cations.

Ionic compound — formed by?

Ions held by electrostatic attraction.

Covalent bond — mechanism?

Atoms share electrons.

Molecule — definition?

Atoms bonded together by covalent bonds.

Diatomic elements — examples?

H₂, N₂, O₂, F₂, Cl₂, Br₂, I₂.

Types of reactions — main?

Synthesis, decomposition, displacement, combustion.

Balancing equations — purpose?

Ensure same atoms on both sides.

Precipitate — formation?

Insoluble solid from solution.

pH scale — measures?

Acidity or alkalinity of solutions.

Indicator — role?

Changes colour with pH.

Litmus paper — colour in acids?

Red.