Chemistry Flashcards
What are the three states of matter?
Solid, liquid, gas
Solid has a definite shape and volume, liquid has a definite volume but changeable shape, gas has both changeable shape and volume.
What are the two types of energy?
Kinetic energy, potential energy
Kinetic energy is energy in action, while potential energy is stored energy.
What is chemical energy?
Energy stored in the bonds of chemical substances
Example includes ATP.
What is an atom?
The smallest stable unit of matter.
What are the three subatomic particles and their charges?
Protons (+), neutrons (neutral), electrons (-).
What determines the atomic number of an element?
The number of protons.
What are the four major elements in the human body?
Oxygen, carbon, hydrogen, nitrogen
These elements make up 96% of body mass.
Name two trace elements important for the human body.
Zinc (Zn), chromium (Cr).
What is an ionic bond?
A bond formed by the transfer of electrons between atoms.
What is a covalent bond?
A bond formed by sharing electrons between atoms.
What is a hydrogen bond?
A weak attraction between a hydrogen atom and an electronegative atom.
What is a synthesis reaction?
A reaction where smaller molecules combine to form larger molecules
Represented as A + B → AB.
What is a decomposition reaction?
A reaction where larger molecules are broken down into smaller parts
Represented as AB → A + B.
What is an exchange reaction?
A reaction where bonds are both made and broken
Represented as AB + C → AC + B.
Why is water considered the ‘universal solvent’?
Its polarity allows it to dissolve many substances.
What is the pH scale?
A scale that measures the concentration of hydrogen ions (H⁺)
Ranges from 0-7 (acidic), 7 (neutral), 7-14 (basic).
What is a buffer?
A chemical that resists changes in pH by neutralizing acids or bases.
What are the four major classes of organic compounds?
Carbohydrates, lipids, proteins, nucleic acids.
What is the primary role of carbohydrates?
To provide a quick and easily used source of energy.
Name three types of lipids.
Triglycerides, phospholipids, steroids.
What are proteins made of?
Amino acids linked by peptide bonds.
What is the role of enzymes?
To act as biological catalysts, speeding up chemical reactions.
What are the two types of nucleic acids?
DNA, RNA.
What is the function of DNA?
To store genetic information and provide instructions for protein synthesis.
