Bio 202 study guide

This atom can form up to _____ single covalent bond(s). An atom with two electron shells. There is one electron pair in the inner electron shell and four unpaired electrons in the outer electron shell. 0 4 2 1 3

4

An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many protons does boron have? 5 11 6 16 0

5

What is the atomic number of an atom that has 6 protons, 6 neutrons, and 6 electrons? 0 18 -1 6 12

6

Fluorine's atomic number is 9 and its atomic mass is 19. How many neutrons does fluorine have? 28 19 10 9 81

10

The innermost electron shell of an atom can hold up to _____ electrons. 8 2 18 1 32

2

What is the maximum number of covalent bonds that an oxygen atom with atomic number 8 can make with hydrogen? 2 6 4 1

2

Which of the following are compounds? H2O, O2, and CH4 O2 and CH4 H2O and O2 H2O and CH4, but not O2

H2O and CH4, but not O2

Which of these relationships is true of an uncharged atom? The number of electrons is equal to the number of neutrons. The atomic mass is equal to the atomic number. The number of neutrons is equal to the number of protons. The atomic mass is equal to the number of electrons. The number of protons is equal to the number of electrons.

The number of protons is equal to the number of electrons.

Which of these refers to atoms with the same atomic number but different atomic masses? These atoms are isotopes. These atoms have different numbers of electrons. These atoms have different numbers of protons. These atoms are different elements. These atoms are isomers.

These atoms are isotopes.

Can the atomic mass of an element vary? No, it is fixed; otherwise a new element will be formed. Yes. Adding or losing neutrons will change the atomic mass without forming a different element. Yes. Adding or losing protons will change the atomic mass without forming a different element. Yes. Adding or losing electrons will substantially change the atomic mass.

Yes. Adding or losing neutrons will change the atomic mass without forming a different element.

An ionic bond involves _____. the unequal sharing of an electron pair an attraction between ions of opposite charge water avoidance no atoms other than sodium and chlorine the sharing of a single pair of electrons

an attraction between ions of opposite charge

Oxygen has an atomic number of 8 and, most commonly, a mass number of 16. Thus, what is the atomic mass of an oxygen atom? approximately 8 daltons approximately 8 grams approximately 16 grams approximately 16 daltons

approximately 16 daltons

Atoms with the same number of protons but with different electrical charges _____. are different isotopes are different ions have different atomic numbers have different numbers of neutrons have different atomic masses

are different ions

What type of bond is joining the two hydrogen atoms? Two hydrogen atoms that share two electrons. ionic covalent hydrophilic hydrophobic hydrogen

covalent

A neutral atom has two, eight, eight electrons in its first, second, and third energy levels. This information ________. does not tell us about the atomic number of the element does not tell us about the size of the element does not tell us about the chemical properties of the element does not tell us about the atomic mass of the element

does not tell us about the atomic mass of the element

A(n) _____ bond joins these two oxygen atoms. Two oxygen atoms with two electron shells. The atoms share four electrons located in their outer electron shells. Each atom also has one electron pair in the inner electron shell and two electron pairs in the outer electron shell. hydrogen quadruple covalent single covalent ionic double covalent

double covalent

The brackets are indicating a(n) _____ bond. A bond between two molecules. Each molecule consists of two small atoms connected to a bigger one. This bond is formed between one small atom from one molecule and the big atom from the other molecule. This small atom has a delta plus charge, and the big atom has a delta minus charge. This bond is marked by three points. hydrogen hydrophobic ionic single (nonpolar) covalent polar covalent

hydrogen

What name is given to the bond between water molecules? polar covalent single (nonpolar) covalent hydrogen ionic hydrophobic

hydrogen

In salt, what is the nature of the bond between sodium and chlorine? hydrogen polar covalent nonpolar covalent ionic hydrophobic

ionic

A(n) _____ refers to two or more atoms held together by covalent bonds. shell ion molecule isotope community

molecule

Bonds between two atoms that are equally electronegative are _____. ionic bonds polar covalent bonds nonpolar covalent bonds hydrogen bonds

nonpolar covalent bonds

An ionic bond is formed when _____. atoms are subjected to radioactive isotopes both atoms are equally attractive to electrons both atoms are electrically neutral one atom transfers an electron to another atom both atoms are nonpolar

one atom transfers an electron to another atom

In the following structure where A and B represent two different elements, the valency of A is ________ and B is ________. Element B is centered, with two electron dots above, one to each side, and one below. On the left and right of B are atoms of A, each with one electron dot between A and B. Below is an atom of A, with an electron dot above it, also between A and B. one; three one; five eight; eight three; five

one; three

Which of the following subatomic particles always has a positive charge? element atom neutron electron proton

proton

What type of bond joins the carbon atom to each of the hydrogen atoms? A molecule that consists of four hydrogen atoms and one carbon atom. Hydrogen atoms are connected to the carbon atom by an electron pair each. These electron pairs are located at the intersection of the electron shell of hydrogens and the outer electron shell of the carbon atom. Moreover, the carbon atom has its own electron pair in the inner electron shell. hydrogen single (nonpolar) covalent ionic double (nonpolar) covalent polar covalent

single (nonpolar) covalent

What determines the types of chemical reactions that an atom participates in? the number of electrons in the innermost electron shell its atomic number the number of protons it contains the number of electrons in the outermost electron shell its atomic mass

the number of electrons in the outermost electron shell

The type of bonding and the numbers of covalent bonds an atom can form with other atoms is determined by _____. the size of the atom; smaller atoms are chemically more reactive the number of protons the nucleus the number of unpaired electrons in the valence shell the number of neutrons

the number of unpaired electrons in the valence shell

#18

to be continued

How many electron pairs are shared between carbon atoms in a molecule that has the formula C2H4? one two three four

two