Intro to Cell and Molec Bio Exam Study Guide
Biology 113 Review sheet
Chapter 2:
* What is a compound and how is it different than an element?
Compound is more than one element. An element cannot be broken down by chem. Rxns. * What are the 4 main elements of life? Why?
C,H,O,N they make up 96% of living matter and they are found in all of the major macromolecules * Be able to calculate the number of protons, neutrons and electrons given an element’s mass number or atomic number. If given this symbol - 4He – can you tell me how many neutrons and protons there are? If given this symbol 12Na – can you tell me how many neutrons and protons there are? Does this element exist? * What is an isotope?
2 atoms of the same element that differ in # neutrons * How are electrons arranged in an atom? Are they paired or unpaired? Which electrons make an element reactive? * How many electrons can reside in each electron shell (first, second and third)? * What are valence electrons and why are they important? * What is valence? What is the valence of carbon, nitrogen, oxygen and hydrogen? This information will not be given to you on the exam and therefore you must know this! * Be able to name the five types of bonds (covalent (2 types), ionic and weak chemical bonds (2 types)). What needs to happen for each of these bonds to be created? For example, for a covalent bond electrons must be shared equally between two elements and these elements will share unpaired valence electrons.
Polar covalent unequal sharing of electrons, nonpolar covalent equal sharing of electrons, ionic transfer of electrons, H-bond between H and O/N/F inter- or intra-molecularly because of the partially positive charge of H and the partially negative charge of O/N/F, Van der Waals between neutral atoms with partially charged regions due to asymmetric electron accumulation by chance. The atoms/molecules must be very close together * What are their similarities and differences? * What happens when a
Chapter 2:
* What is a compound and how is it different than an element?
Compound is more than one element. An element cannot be broken down by chem. Rxns. * What are the 4 main elements of life? Why?
C,H,O,N they make up 96% of living matter and they are found in all of the major macromolecules * Be able to calculate the number of protons, neutrons and electrons given an element’s mass number or atomic number. If given this symbol - 4He – can you tell me how many neutrons and protons there are? If given this symbol 12Na – can you tell me how many neutrons and protons there are? Does this element exist? * What is an isotope?
2 atoms of the same element that differ in # neutrons * How are electrons arranged in an atom? Are they paired or unpaired? Which electrons make an element reactive? * How many electrons can reside in each electron shell (first, second and third)? * What are valence electrons and why are they important? * What is valence? What is the valence of carbon, nitrogen, oxygen and hydrogen? This information will not be given to you on the exam and therefore you must know this! * Be able to name the five types of bonds (covalent (2 types), ionic and weak chemical bonds (2 types)). What needs to happen for each of these bonds to be created? For example, for a covalent bond electrons must be shared equally between two elements and these elements will share unpaired valence electrons.
Polar covalent unequal sharing of electrons, nonpolar covalent equal sharing of electrons, ionic transfer of electrons, H-bond between H and O/N/F inter- or intra-molecularly because of the partially positive charge of H and the partially negative charge of O/N/F, Van der Waals between neutral atoms with partially charged regions due to asymmetric electron accumulation by chance. The atoms/molecules must be very close together * What are their similarities and differences? * What happens when a