Chemistry EOY Flashcards
(26 cards)
What are the states of matter?
Solids: Particles tightly packed in fixed positions, only vibrate, low energy.
Liquids: Particles close together but move randomly, medium energy.
Gases: Particles far apart and move fast and randomly, high energy.
What happens during changes of state?
Melting/Boiling: Energy added.
Freezing/Condensation: Energy removed.
What is diffusion?
Movement of particles from high to low concentration. Happens faster in gases due to more particle movement.
Example: Bromine gas spreads in a jar without stirring.
What are the subatomic particles?
Proton: Charge +1, mass 1, in the nucleus.
Neutron: Charge 0, mass 1, in the nucleus.
Electron: Charge -1, tiny mass, orbits nucleus.
What is the atomic number and mass number?
Atomic number = number of protons.
Mass number = protons + neutrons.
What are isotopes?
Atoms of the same element with the same protons but different neutrons.
Example: Carbon-12 vs Carbon-14.
What is the electron configuration for Carbon?
First shell: max 2 electrons.
Second shell: max 8.
Third shell: max 8.
Example: Carbon = 6 electrons → 2, 4.
What is ionic bonding?
Ionic bonding occurs between a metal and a non-metal. Metals lose electrons → become positive ions (cations). Non-metals gain electrons → become negative ions (anions). Opposite charges attract to form an ionic bond.
What are the properties of ionic compounds?
High melting and boiling points due to strong bonds. Conduct electricity when molten or dissolved. Usually soluble in water.
What is an example of ionic bonding?
Sodium (Na) loses 1 electron → Na⁺. Chlorine (Cl) gains 1 electron → Cl⁻. Ionic compound = NaCl.
What are the flame test colors for positive metal ions?
Lithium: Crimson red.
Sodium: Yellow.
Potassium: Lilac.
Calcium: Brick red.
Copper: Green.
What are the sodium hydroxide precipitate tests?
Copper(II) → Blue precipitate.
Iron(II) → Green precipitate.
Iron(III) → Brown precipitate.
What are the tests for negative ions?
Carbonate (CO₃²⁻): Add acid → fizzing (CO₂ released) → limewater turns milky.
Sulfate (SO₄²⁻): Add HCl then barium chloride → white precipitate.
Chloride (Cl⁻): Add nitric acid then silver nitrate → white precipitate.
What are the characteristics of acids and alkalis?
Acids: Produce H⁺ ions, pH < 7.
Alkalis: Produce OH⁻ ions, pH > 7.
Neutral = pH 7.
What are the helpful acronyms for reactions?
MASH: Metal + Acid → Salt + Hydrogen.
BAWS: Base + Acid → Water + Salt.
AAWS: Alkali + Acid → Water + Salt.
CAWCS: Carbonate + Acid → Water + CO₂ + Salt.
What are the solubility rules?
Soluble: All nitrates, all group 1 and ammonium salts, most chlorides and sulfates.
Insoluble: Most carbonates and hydroxides (except group 1 or ammonium ones).
What are the three methods to make salts?
- Acid + Base (e.g. HCl + CuO): Heat, add base, filter, then evaporate.
- Acid + Metal (e.g. H₂SO₄ + Mg): React, filter out excess metal, evaporate.
- Precipitation: Mix two soluble salts to form an insoluble salt.
What are examples of making salts?
Hydrochloric acid + sodium hydroxide → sodium chloride + water.
Sulfuric acid + copper oxide → copper sulfate + water.
Hydrochloric acid + calcium carbonate → calcium chloride + CO₂ + water.
What does the rate of reaction mean?
How fast a chemical reaction occurs.
What are ways to measure reaction rate?
Use a gas syringe to measure gas volume. Measure mass loss if gas escapes. Time how long it takes for a colour change or precipitate to appear.
What factors affect reaction rate?
Temperature: Higher temp = faster reaction (particles move faster).
Concentration: More particles = more collisions.
Surface area: Smaller pieces = faster reaction.
Catalyst: Speeds up the reaction without being used up.
What is collision theory?
Particles must collide with enough energy (activation energy). Increasing frequency and energy of collisions speeds up the reaction.
What are the properties of Group 1 alkali metals?
Soft, shiny metals. Low density (first 3 float on water). Stored in oil to prevent reaction with air. Very reactive – reactivity increases down the group.
What is the general reaction of alkali metals with water?
Metal + Water → Metal hydroxide + Hydrogen.
