States of Matter & Phase Changes
What are the four main states of matter?
Solid, liquid, gas, and plasma.
What is the smallest unit of matter?
Atom.
What type of bond occurs when electrons are shared?
Covalent bond.
What is the pH scale used to measure?
The acidity or alkalinity of a solution.
What is the substance that dissolves in a solution called?
Solute.
What element is the basis of organic chemistry?
Carbon.
What phase change occurs when a liquid turns into a gas?
Evaporation.
What subatomic particle has a positive charge?
Proton.
What type of bond occurs when electrons are transferred?
Ionic bond.
What is the pH of pure water?
7 (neutral).
hat is the substance that dissolves the solute?
Solvent.
What are the four major types of biomolecules?
Carbohydrates, lipids, proteins, and nucleic acids.
What process turns a solid directly into a gas?
Sublimation.
What is the center of an atom called?
Nucleus.
What are the substances present before a chemical reaction called?
Reactants.
What do acids release in solution?
Hydrogen ions (H⁺).
What type of mixture has uniform composition?
Homogeneous mixture.
What is the function of DNA?
Stores genetic information.
What happens to molecular motion as temperature increases?
Molecules move faster.
What type of subatomic particle orbits the nucleus?
Electron.
What is the law that states matter cannot be created or destroyed?
Law of Conservation of Mass.
What do bases release in solution?
Hydroxide ions (OH⁻).
What type of mixture has visible differences?
Heterogeneous mixture.
What type of biomolecule speeds up chemical reactions?
Enzyme (protein).
What phase change occurs when water freezes?
Solidification.
What determines an element’s atomic number?
The number of protons.
What type of chemical reaction absorbs heat?
Endothermic reaction.
What is an example of a strong acid?
Hydrochloric acid (HCl).
What is the process of separating liquids based on boiling points?
Distillation
What type of organic molecule forms cell membranes?
Lipids.