LATEST BIOLOGY 1010 EXAM 2 QUESTIONS
WITH CORRET ANSWERS
1. Be able to differentiate between the terms atom, element, molecule, and
compound. - ANSWER Atom- the most basic unit of matter that still retains its
unique properties
Molecule - two or more atoms bonded together
Element - one kind of atom (eg. Au=gold)
Compound - a molecule (two or more atoms bonded together) that contains at
least two different kinds of atoms
2. Know the general structure of an atom. -Know the charges and relative
masses of protons,
neutrons and electrons. - ANSWER proton (+1 charge; 1 mass)
Neutro (0 charge; 1 mass)
Electron (-1 charge; 1/1836)
3. Know how to interpret the information on the periodic table of the elements.
You should be able to
determine how many protons, neutrons, and electrons an atom has, based on
information given. - ANSWER Protons= electrons = 6
Atomic mass = 12.0107
Neutrons= mass - protons
4. What is an isotope? - ANSWER atoms of the same element (have the same
atomic number) that have different numbers of neutrons
, 5. Be able to describe some applications of radioactive isotopes; such as,
medical uses and carbon dating. - ANSWER Radiation therapy, which uses
high-energy radiation to kill cancer cells by damaging their DNA; radiotracers
emit gamma radiation as it decays; carbon dating (living things contain a fixed
ration of radioactive carbon, 14, and non-radioactive carbon, 12.
6. What is meant by the term half-life? If given the half-life of an isotope, be
able to calculate how much of the
unstable isotope and stable decay product are present after a certain period of
time. - ANSWER Half-life = length of time until half of the material decays
Ex: 2,200/2 (1 half-life) → 1,100/2 → 550/2 →275;
if asking for decay: 2200 - 275=1925
7. What four elements, taken together, are the most abundant elements found in
living organisms? - ANSWER carbon, hydrogen, oxygen, and nitrogen
8. Which of the following is true about an atom? - ANSWER An atom is stable
when its outermost electron shell is completely filled.
9. What are some of the differences between ionic, covalent and hydrogen
bonds? How do these bonds form? - ANSWER Ionic bond → one atom
transfers completely one or more electrons to another. The result is two
oppositely charged ions; the two ions attract each other, forming a compound.
Covalent bonds → electrons are shared either equally or unequally. The nuclei
come closer together and the two electrons begin to circle around both of them.
(Strongest out of 3 types of bonds)
WITH CORRET ANSWERS
1. Be able to differentiate between the terms atom, element, molecule, and
compound. - ANSWER Atom- the most basic unit of matter that still retains its
unique properties
Molecule - two or more atoms bonded together
Element - one kind of atom (eg. Au=gold)
Compound - a molecule (two or more atoms bonded together) that contains at
least two different kinds of atoms
2. Know the general structure of an atom. -Know the charges and relative
masses of protons,
neutrons and electrons. - ANSWER proton (+1 charge; 1 mass)
Neutro (0 charge; 1 mass)
Electron (-1 charge; 1/1836)
3. Know how to interpret the information on the periodic table of the elements.
You should be able to
determine how many protons, neutrons, and electrons an atom has, based on
information given. - ANSWER Protons= electrons = 6
Atomic mass = 12.0107
Neutrons= mass - protons
4. What is an isotope? - ANSWER atoms of the same element (have the same
atomic number) that have different numbers of neutrons
, 5. Be able to describe some applications of radioactive isotopes; such as,
medical uses and carbon dating. - ANSWER Radiation therapy, which uses
high-energy radiation to kill cancer cells by damaging their DNA; radiotracers
emit gamma radiation as it decays; carbon dating (living things contain a fixed
ration of radioactive carbon, 14, and non-radioactive carbon, 12.
6. What is meant by the term half-life? If given the half-life of an isotope, be
able to calculate how much of the
unstable isotope and stable decay product are present after a certain period of
time. - ANSWER Half-life = length of time until half of the material decays
Ex: 2,200/2 (1 half-life) → 1,100/2 → 550/2 →275;
if asking for decay: 2200 - 275=1925
7. What four elements, taken together, are the most abundant elements found in
living organisms? - ANSWER carbon, hydrogen, oxygen, and nitrogen
8. Which of the following is true about an atom? - ANSWER An atom is stable
when its outermost electron shell is completely filled.
9. What are some of the differences between ionic, covalent and hydrogen
bonds? How do these bonds form? - ANSWER Ionic bond → one atom
transfers completely one or more electrons to another. The result is two
oppositely charged ions; the two ions attract each other, forming a compound.
Covalent bonds → electrons are shared either equally or unequally. The nuclei
come closer together and the two electrons begin to circle around both of them.
(Strongest out of 3 types of bonds)
