Matter
Is salt an element, compound, or mixture?
Salt is a compound.
___ H₂ + ___ O₂ → ___ H₂O
2H₂ + O₂ → 2H₂O
What type of reaction is: acid + base → salt + water?
A neutralisation reaction
Is a pH level of 9 more acidic or basic than a pH level of 3?
A pH level of 9 is more basic than a pH level of 3.
Can acid rain damage buildings?
Yes
Name the type of matter made from two or more substances not chemically bonded.
A mixture.
Create the word equation for the following chemical equation: Mg + 2HCl --> MgCl2 + H2
Magnesium + Hydrochloric acid --> Magnesium chloride + Hydrogen
What is the difference between an endothermic reaction and an exothermic reaction?
An endothermic reaction absorbs energy from its surroundings, causing the environment to cool down. In contrast, an exothermic reaction releases energy into its surroundings, often in the form of heat or light, causing the temperature to rise.
What color does a universal indicator turn when a solution has a pH of 4?
A universal indicator will turn orange when a solution has a pH of 4.
What type of pollution causes acid rain
Air pollution
What is the difference between a molecule and a compound?
A molecule is a group of two or more atoms bonded together. A compound is a specific type of molecule made of atoms from two or more different elements.
Write the word equation for iron reacting with oxygen to form rust.
Iron + oxygen → iron oxide
Identify the reaction type: Zn + CuSO₄ → ZnSO₄ + Cu
Single displacement
What is the pH level of a solution with a hydrogen ion concentration of 10-3?
The solution has a pH level of 3
Which two major gases contribute to acid rain?
Sulfur dioxide and nitrogen oxides
Is air a homogeneous or heterogeneous mixture.
Air is a homogeneous mixture.
Write the word equation for methane combustion.
Methane + oxygen → carbon dioxide + water
Identify the reaction type: CaCO₃ → CaO + CO₂
A decomposition reaction
How much more acidic does the solution become if the pH changes from 4 to 2?
A solution becomes 100 times more acidic when the pH changes from 4 to 2. [1, 2]
Explain how acid rain affects aquatic ecosystems.
Acid rain harms aquatic ecosystems by lowering the water's pH and leaching toxic aluminum from surrounding soils. This acidic and metal-rich runoff causes reproductive failure in fish, damages the gills of adults, and starves ecosystems by wiping out foundational species, leading to a catastrophic collapse of the food web.
Explain why water is both a molecule and a compound.
Water contains bonded atoms and different elements chemically combined
___ C₃₁H₆₄ + ___ O₂ → ___ CO₂ + ___ H₂O
C₃₁H₆₄ + 47O₂ → 31CO₂ + 32H₂O
Explain the difference between synthesis and decomposition reactions.
Synthesis and decomposition reactions are exact chemical opposites. Synthesis reactions combine two or more simpler substances to form a single, more complex product (e.g. A + B --> AB). Decomposition reactions break a single, complex compound down into two or more simpler substances (e.g. AB --> A + B).
Explain why acids conduct electricity.
Acids conduct electricity because they ionize in water, breaking down into freely moving charged particles called ions. These charged ions act as carriers of electric charge, allowing an electric current to flow through the solution.
A forest near several coal-burning power plants begins losing trees, while nearby lakes show decreasing biodiversity and lower pH levels. Explain the chemical process causing these environmental changes and why the effects spread far from the original pollution source.
Sulfur dioxide and nitrogen oxides react with water vapor in the atmosphere to form sulfuric and nitric acids, which are carried by winds and fall as acid rain, damaging soil, plants, and aquatic ecosystems?