Questions and Answers
What is an ion?
An ion is when two or more atoms share electrons and have a stable connection, typically formed between nonmetals and metals.
Which of the following is a polyatomic ion?
Water in solid form is known as ______.
ice
The chemical formula for Ozone is ______.
Signup and view all the answers
What does it mean for a chemical equation to be balanced?
Signup and view all the answers
Which of the following metals do not oxidize under any circumstance?
Signup and view all the answers
Metals react rapidly with oxygen.
Signup and view all the answers
Which of these elements is an allotrope of carbon?
Signup and view all the answers
What product is formed when sulfur reacts with oxygen?
Signup and view all the answers
What is the purpose of a catalyst in a chemical reaction?
Signup and view all the answers
Acids release ______ ions in solution.
Signup and view all the answers
What type of reaction occurs when two chemicals combine?
Signup and view all the answers
Which of the following is a product of fermentation?
Signup and view all the answers
Ozone (O3) protects the Earth from harmful UV light.
Signup and view all the answers
______ is a natural yellow gas that is poisonous.
Signup and view all the answers
What is produced when an acid neutralizes a base?
Signup and view all the answers
Study Notes
Ions
- Ions result from atoms sharing electrons, typically formed between metals and nonmetals (e.g., NaCl).
- Positive ions (cations) occur when atoms lose electrons; negative ions (anions) occur when atoms gain electrons.
- Polyatomic ions consist of two or more atoms, such as nitrate (NO2^-1).
Chemical Reactions
- Water exists in three forms: solid (ice, H2O (s)), liquid (water, H2O (l)), and gas (steam, H2O (g)).
- Solutions containing dissolved substances are termed aqueous solutions (e.g., NaCl (aq)).
- A balanced chemical equation has equal numbers of each type of atom on both sides (e.g., CaCO3 → CaO + CO2).
- Balancing requires adjusting coefficients to ensure atom counts match on both sides of the equation (e.g., 2H2O2 → O2 + 2H2O).
Metals, Non-Metals, and Their Properties
Alloys
- Alloys are metallic mixtures, improving properties like strength and durability (e.g., copper alloys).
Activity Series
- Metals are reactive in the order: Sodium, Lithium, Calcium, Magnesium, Aluminium, Zinc, Iron, Lead, (Hydrogen), Copper, Silver, Gold.
Reactions with Oxygen
- Reactive metals (e.g., sodium, magnesium) form metal oxides rapidly when exposed to oxygen (e.g., 2Mg + O2 → 2MgO).
- Less reactive metals (e.g., lead, copper) oxidize slowly.
Reactions with Water
- Reactive metals generate metal hydroxides and hydrogen gas when reacting with water (e.g., 2Li + 2H2O → Li2OH + H2).
- Cold water reactions are slower for certain metals, like potassium.
Non-Metals, Allotropes, and Their Properties
- Non-metals lack metallic properties (e.g., lustre, malleability) and are poor electrical conductors, except graphite.
- Allotropes are different physical forms of elements (e.g., carbon forms include diamond and graphite).
Oxygen
- Oxygen, a non-metal gas (21% of Earth's atmosphere), supports combustion and creates ozone (O3) when electrified.
- Ozone protects against UV radiation and is used for pool sanitization.
Carbon Allotropes
- Diamond is hard and used in cutting tools and jewelry; its structure contributes to its hardness.
Chlorine
- Chlorine is a toxic yellow gas used for water purification and produces hypochlorous acid in water.
- Sodium hydroxide with chlorine creates bleach (NaOCl).
Nitrogen
- Nitrogen makes up 78% of the atmosphere, is unreactive, and forms nitric oxide when lightning occurs.
Sulphur
- Sulphur is a brittle solid often found near volcanoes and creates sulphur dioxide (SO2) when burned with oxygen.
Covalent Bonding
- Covalent bonds involve non-metals sharing electrons, forming strong connections.
- Bonds can be single, double, or triple, with increased bonds leading to stronger interactions.
Acids, Bases, and Neutralization
- The pH scale (1 to 14) indicates acidity; lower pH means higher acidity.
- Acids yield H+ in solutions; bases yield OH- ions, while neutral solutions have a pH of 7.
- Neutralization occurs when acids and bases react to form water and salts (e.g., HCl + NaOH → NaCl + H2O).
Organic Chemistry
- Organic chemistry focuses on carbon and its compounds; hydrocarbons have only carbon and hydrogen.
- Alkanes are hydrocarbons following the formula CnH2n+2; they are combustible.
- Polymers consist of repeating monomers; polymerization converts monomers into polymers like polyethylene.
Types of Reactions
- Combination reactions merge two substances (e.g., Na + Cl → NaCl).
- Decomposition reactions break down compounds into simpler substances (e.g., CuCO3 → CuO + CO2).
- Displacement reactions involve one substance replacing another within a compound.
Precipitate and Spectator Ions
- A precipitate forms when at least one reactant is aqueous, producing a solid (e.g., calcium sulfate).
- Spectator ions remain unchanged throughout the reaction; simplifying equations involves canceling them.
Summary
- Understanding these concepts forms a foundation for NCEA Level 1 Chemistry, encompassing ion formation, chemical reactions, properties of elements, organic chemistry, and types of chemical reactions.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the non-official notes created for NCEA Level 1 Chemistry. This resource includes valuable insights and humor, potentially featuring some Ethan jokes. Ideal for anyone looking to enhance their understanding of basic chemistry concepts.
