Matter Classification
What type of mixture has different substances that are visibly distinguishable?
Heterogeneous mixture
What does a chemical equation represent?
The substances before and after a chemical reaction
What force holds water molecules together?
Cohesion
What is the pH of an acid?
Less than 7
What law states that matter cannot be created or destroyed during a chemical reaction?
Law of Conservation of Mass
Carbon dioxide (CO₂) is what type of matter?
Compound
In 2H₂ + O₂ → 2H₂O, what must be the same on both sides?
The number and types of atoms
What two properties of water help move water through plant xylem?
Cohesion and adhesion
What is the pH range of bases?
Greater than 7
35 g of one substance reacts with 15 g of another in a closed container. What is the total mass?
50 g
Saltwater is what type of mixture?
Homogeneous mixture
How many oxygen atoms are in 3Ca(OH)₂?
6
What property allows water droplets to resist being pulled apart?
Surface tension
Red litmus paper turns blue when placed in what type of substance?
Base
If a reaction starts with 100 g of reactants, how much total product should form in a closed system?
100 g
Gravel mixed with water is what type of mixture?
Heterogeneous mixture
In Ca + Cl₂ → CaCl₂, what elements are present?
Calcium and chlorine
What is the attraction between water and another type of molecule called?
Adhesion
Which generally has a lower pH: lemon juice or black coffee?
Lemon juice
During a chemical reaction, a ring loses mass while the solution gains mass. What happens to the total mass?
It stays the same
What is the difference between a compound and a mixture?
A compound is chemically bonded; a mixture contains substances physically combined
In 3Hg(OH)₂ + 2H₃PO₄ → Hg₃(PO₄)₂ + 6H₂O, what does the chemical equation show?
Reactants rearrange their atoms to form new products while conserving atoms
Explain how cohesion and adhesion work together to move water upward through a plant.
Cohesion keeps water molecules connected while adhesion helps them stick to xylem walls
A substance has a pH of 3. Is it an acid or a base, and how do you know?
Acid; its pH is below 7
Why does the total mass remain constant during a chemical reaction in a closed system?
Atoms are rearranged but are not created or destroyed