Matter and Atomic Structure Quiz

Matter and Atomic Structure

• Matter has mass and occupies space. Atoms make up matter.
• There are 92 naturally occurring elements.
• Atoms are mostly empty space.
• Atoms are composed of protons, neutrons, and electrons.
• Protons and neutrons are in the nucleus. They have a positive charge and neutrons have no charge.
• Electrons orbit the nucleus and have a negative charge.
• The number of protons equals the number of electrons.
• Atomic number is the number of protons.
• Atomic mass is the number of protons plus the number of neutrons.
• Electrons fill electron shells.

Composition of Matter

• Number of protons = number of electrons
• Atomic number = number of protons
• Atomic mass = weight of atom = protons + neutrons
• Atoms strive to be stable with full electron shells. Stability often involves bonding with other atoms.

Chemical Bonding

• Atoms bond to become stable.
• Valence electrons are involved in bonding.
• Covalent bonds involve sharing electrons.
• Ionic bonds involve transferring electrons.

Chemicals in the Body

• Human body is composed mainly of carbon, hydrogen, oxygen, and nitrogen (96%).
• Other elements (iron, calcium, etc.) make up the remaining 4%
• Carbon forms the foundation of many body structures due to its ability to form multiple bonds.
• Key is filling up the valence shell.

Attractions Between Molecules

• Opposite charges attract, like charges repel.
• Polar molecules have uneven distribution of charge, creating regions of positive and negative charge.
• Polarity causes some molecules to remain attracted to each other.
• Nonpolar molecules have an equal distribution of charges.

Hydrogen Bonding

• A special kind of attractive force in polar molecules
• Occurs between hydrogen and oxygen, nitrogen, or fluorine in neighboring molecules.

pH Scale

• Measures acidity or alkalinity of a substance.
• Ranges from 0 to 14, with 7 being neutral.
• Acids have a pH less than 7.
• Bases have a pH greater than 7.

Organic vs Inorganic

• Inorganic compounds do not contain carbon.
• Organic compounds typically contain carbon and hydrogen.
• Many of the chemicals in the body are organic.

Carbohydrates

• Monosaccharides are simple sugars (single sugars).
• Disaccharides are double sugars (two simple sugars).
• Polysaccharides are complex carbohydrates (multiple sugars).
• Key examples include starch, glycogen, and cellulose.

Lipids

• Triglycerides are energy storage molecules.
• Phospholipids are important in cell membranes.
• Steroids have diverse functions, including hormone production.
• Waxes provide protection and structure.

Nucleic Acids

• DNA and RNA carry genetic information.
• DNA uses the bases adenine, thymine, guanine, and cytosine.
• RNA uses adenine, uracil, guanine, and cytosine.

Proteins

• Polymers composed of amino acids.
• The specific sequence of amino acids determines a protein's 3-dimensional structure and function.
• The folding of proteins is crucial to their function.