Chapter 2 CHEMISTRY OF LIFE Flashcards
Matter
is anything that has mass and takes up space.
Elements
are the basic building blocks of matter that cannot be broken down by chemical means.
Atoms
re the smallest units of an element that retain the element’s physical and chemical properties.
Neutrons
are neutral in nucleus.
Protons
are positively charged in nucleus.
Electrons
are negatively charged and orbit around the nucleus.
Isotopes
are atoms that have the same atomic number but a different atomic mass because the number of neutrons differ.
Radioisotopes
are useful in dating old objects, imaging body organs and tissues through X-rays, and killing cancer cells.
IONIC BONDS
Atoms in this type of bond donate or take on electrons. Result in a stable outer shell.
Occur between particles that are charged (ions)
Covalent bonds
Atoms in this type of bond share electrons. Result in a stable outer shell
WHAT ARE THE PROPERTIES OF WATER?
Water is liquid at room temperature.
Liquid water does not change temperature quickly. Water has a high heat of evaporation.
Frozen water is less dense than liquid water. Molecules of water cling together.
Water is a solvent for polar molecules.
WHAT BOND HOLDS WATER MOLECULES TOGETHER?
Hydrogen bonds occur between a hydrogen in a covalent bond and
a negatively charged atom
Acids
substances that dissociate and release hydrogen ions (H+).
0-6
Bases
ubstances that take up hydrogen ions (H+) or release hydroxide ions (OH-). 8-14
Hydrolysis reaction
the addition of water that breaks larger molecules into their subunits