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Flashcards in Ch. 2 Deck (54)
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1

What is the smallest particle of an element that still retains its distinctive chemical properties?

Atom

2

Which type of subatomic particle is NOT in the nucleus of an atom?
A. Electrons
B. Protons
C. Neutrons

Electrons

3

The atomic number of an element is determined by the number of what type of particle in the atom’s nucleus?

Protons

4

In an atom, the number of positively charged protons is the same as the number of:

negatively charged electrons.

5

Which subatomic particles have essentially the same mass?
A. Protons and neutrons
B. Protons and electrons
C. Electrons and neutrons

Protons and Neutrons

6

Isotopes of the same element have different numbers of what type of subatomic particle?

Neutrons

7

The atomic weight of an atom is its mass relative to which of the following atoms?
A. Hydrogen
B. Helium
C. Carbon

Hydrogen

8

How much does a mole of carbon atoms (having an atomic weight of 12) weigh?

12 grams

9

In living organisms, four elements make up 96.5% of an organisms weight. What are these four elements?

Carbon, hydrogen, nitrogen, and oxygen

10

Which subatomic particles undergo rearrangements when atoms combine with others to form molecules?
A. Protons
B. Neutrons
C. Electrons

Electrons

11

T or F: The atoms found in living tissues all have complete outer electron shells and are therefore quite stable on their own.

False

12

What type of bond is formed when two atoms share electrons?

A covalent bond

13

What type of bond is formed when one atom donates electrons to another atom?

An ionic bond

14

14.What dictates the number of bonds an atom can make?
A. The number of protons in its nucleus
B. The state of its outermost electron shell
C. The state of its innermost electron shell

The state of its outermost electron shell

15

An oxygen atom, with 6 electrons (of a possible 8) in its outer electron shell, has the capacity to form a maximum of how many covalent bonds?

2

16

Which type of covalent bond allows for rotation about the bond axis?
A. Single bond
B. Double bond
C. Triple bond

Single bond

17

Which term describes a covalent bond in which electrons are shared unequally?
A. Nonpolar
B. Polar
C. Ionic

Polar

18

Which of the following covalent bonds is nonpolar?
A. The bond between oxygen and hydrogen, –O–H
B. The bond between nitrogen and hydrogen, –N–H
C. The bond between carbon and hydrogen, –C–H

The bond between carbon and hydrogen, –C–H

19

Which type of bond is the strongest?
A. Ionic
B. Hydrogen
C. Covalent

Covalent Bond

20

Which of the following atoms is most likely to participate in an ionic bond?
A. Carbon, with an outer electron shell filled with 4 of a possible 8 electrons
B. Phosphorus, with an outer electron shell filled with 5 of a possible 8 electrons
C. Chlorine, with an outer electron shell filled with 7 of a possible 8 electrons

Chlorine, with an outer electron shell filled with 7 of a possible 8 electrons

21

What are substances held together solely by ionic bonds generally called?

Salts

22

T or F: Electrostatic attractions are stronger than covalent bonds.

False

23

In water, hydrogen bonds form between:

a hydrogen atom and an oxygen atom.

24

Consider an O–H covalent bond in H2O. Which atom more strongly attracts electrons and acquires a partial negative charge?

Oxygen

25

Hydrophilic molecules:

mix well with water

26

Which statement is true?
A. Substances that release protons when they dissolve in water are termed acids and result in a pH higher than 7.
B. Substances that release protons when they dissolve in water are termed bases and result in a pH higher than 7.
C. Substances that release protons when they dissolve in water are termed acids and result in a pH lower than 7.

Substances that release protons when they dissolve in water are termed acids and result in a pH lower than 7.

27

Which of the following substances is a weak acid?
A. Glucose
B. HCl
C. Acetic acid
D. Adenine

Acetic Acid

28

Which is NOT true of a base?
A. A base is the opposite of an acid.
B. A base has a pH lower than 7.
C. A base is any molecule capable of accepting a proton.

A base has a pH lower than 7.

29

Which substance is considered organic?
A. H2O (water)
B. CH4 (methane)
C. NaCl (table salt)

CH4 (Methane)

30

Carbon, which has four electrons in its outer shell (capacity 8 electrons), can form a maximum of how many covalent bonds with other atoms?

4