Chapter 2 Study Guide Flashcards
(89 cards)
What is the major constituent of all living things?
Water
Water makes up what % of the total body weight for the average adult?
65% to 75%
What are the 2 major water compartments?
Intracellular compartments and extracellular compartments
What solutes can you find dissolved in the body waters?
Organic: Carbohydrates, lipids, proteins, and nucleic acids
Inorganic molecules and ions (atoms with a net charge)
What is the Universe made up of?
Matter
What is the definition for “mass”?
Mass is how much matter there is in an element.
How many different kinds of matter occur naturally?_____________ What do we call these different types?___________
92 different kinds of matter occur naturally, these are called elements.
Define “atoms”. What do atoms consist of?
Atoms are the smallest unit of the chemical elements. It consists of a nucleus, which has two types of particles Protons (positive charged), Neutrons (neutral charged)
What sub-atomic particles can you find in the nucleus?
Protrons and Neutrons
Where do you find virtually all of an atom’s mass?
Most of the atom’s mass is located in the nucleus.
What is the mass number for: Protons? Neutrons? Electrons?
For any element:
Number of Protons = Atomic Number
Number of Electrons = Number of Protons = Atomic Number
Number of Neutrons = Mass Number - Atomic Number
What does the atomic number (elemental #) tell you about an atom?
The Atomic number (elemental #) tells you the number of protons.
What is the electrical charge on: Protons? Neutrons? Electrons?
P = + / E = - / N = no charge
What is the relationship between the # of protons and electrons?
The protons are equal to the number of electrons.
What are isotopes?
Isotopes are different forms of a particular atom. E.g. Cl atoms
Define the following terms: molecules, compounds.
- Molecules:* two or more atoms held together by a chemical bond
- **Compounds: *** two or more elements (H2O)
The atoms making up a molecule are held together by chemical bonds. Name and describe 4 chemical bonds we will be using
- Molecules:* interaction of the valence electrons between two or more atoms.
- Covalent Bonds:* when atoms share their valence electrons. Formed between identical atoms. Nonpolar electrons equally distributed; polar electrons positive and negative.
- Ionic Bonds: * when one ore more valence electrons from one atom are completely transferred to a second atom.
- **Hydrogen Bonds: *** Hydrogen always bonds with F, N, O. Forms when a Hydrogen atoms forms a polar covalent bond with O or N and H gains a slight positive charge as the electron is pulled toward the other atom. These hold DNA proteins
What are ions? Cations? Anions?
Ions: Atoms or molecules that have positive or negative charges.
Cations: Positively charged ions
Anion: negatively charged
These form an ionic compound NaCl
How may bonds will carbon always make? Oxygen? Hydrogen?
Carbon always forms 4 bonds
Oxygen always forms 2 bonds
Hydrogen always forms 1 bond
In what 2 places might we find “hydrogen bonds” used?
The holding of DNA proteins
Hydrogen Bonds can also be formed between adjacent water molecules, which are responsible for surface tension and capillary action.
What are “hydration spheres”?
Hydration spheres make an ion or a molecule water soluble. Dissociation of the ionic compound NaCl yields Na+ Cl-. Each of these ions attracts polar water molecules. The water molecules that surround these ions in turn attract other molecules of water to form hydration spheres around each ion.
Define: Dissolve. Dissociation
When a substance splits into simpler molecules when put in water and do not recombine to give original substance then we say it dissolves in water. Ex: sugar dissolves in water.
If a substance breaks up when put in water and reunites to give original substance then we say dissociates in water they can associate to give back original sub. Ex: Acetic acid when mixed with water dissociates into acetate ions and hydrogen ions. CH3COOH = CH3COO- + H+
Water itself can dissociate into what 2 ions?_________ & ___________
H & OH
What is the definition of an: Acid? Base?
- Acid* – is a compound that when placed in water will release a Hydrogen ion. (H)
- Base* – is a compound that absorbs Hydrogen ions. (OH)