Ch 6 Section 3 Flashcards Preview

Chem > Ch 6 Section 3 > Flashcards

Flashcards in Ch 6 Section 3 Deck (54):
1

A familiar example of an ionically bonded compound is

Sodium chloride

2

A sodium atom, NA+ has a charge of

1+

3

A chloride ion, Cl- has a charge of

1-

4

There is an electrical force of attraction between

Oppositely charged ions

5

In sodium chloride the oppositely charged ions combine in a one to one ratio so that each positive charge is

Balanced by a negative charge

6

An ionic compound is composed of positive and negative ions that are

Combined so that the numbers of positive and negative charges are equal

7

Most ionic compounds exist as

Crystalline solids

8

A crystal of any ionic compound is a 3-dimensional network of

Positive and negative ions mutually attracted to one another

9

In contrast to a molecular compound an ionic compound is not composed of

Independent neutral units that can be isolated and examine s

10

The chemical formula of an ionic compound merely represents the

Simplest ratio is the compounds combined ions that gives electrical neutrality

11

The chemical formula of an ionic compound shows the ratio of the i

Ions present in a sample of any size

12

A formula unit is the simplest collection of atoms from which an

Ionic compounds formula can be established

13

In the naming of a monatomic anion the ending of the elements name is replaced with

-ide

14

Most of the rocks and minerals that make up earths crust consist of

Positive and negative ions held together by ionic bonding

15

The ratio of ions in a formula unit depends on the

Charles of the ions combined

16

Electron for notation can be used to demonstrate the

Changes that take place in ionic bonding

17

Ionic compounds do not ordinarily form by the

Combination of isolated atoms

18

Atoms it sodium and other alkali metals readily lose one electron to

Form cations

19

Atoms of chlorine and other halogens readily gain one electron to

Form anions

20

The combination of sodium and chlorine atoms to produce one formula unit of sodium chloride can be represented as follows

Sodium atom + chlorine atom --> sodium cation + chlorine anion

(Refer to txtbk for electron dot notation)

21

The transfer of an electron from the sodium atom to the chlorine atom transforms each atom into an ion with a

Noble gas configuration

22

In an ionic crystal ions minimize their potential energy by combining in an

Orderly arrangement known as a crystal lattice

23

The attractive forces at work within an ionic crystal include those between

Oppositely charged and those between the nuclei and electrons of adjacent ions

24

The repulsive forces at work within an ionic crystal include those between

Like-charged ions and those between electrons of adjacent ions

25

The distances between ions and their arrangement in a crystal represent a

Balance among all these forced

26

In NaCl attraction between the adjacent oppositely charged ions is much stronger than

Repulsion by other ions or the same charge which are farther away

27

The 3-dimensional arrangements of ions and the strength of attraction between them vary with the

Sizes and charges of the hind and the numbers of ions of different charges

28

To compare bond strengths in ionic compounds chemists compare the amounts of energy

Releases when separated ions in a gas come together to form a crystalline solid

29

Lattice energy is the energy released when one

Nike of an ionic crystalline compound is formed from gaseous ions

30

The negative lattice energy values indicate that energy is

Released when the crystals are formed

31

The force that holds ions together in ionic compound is a very strong overall

Attraction. Between positive and negative charges

32

The forces of attraction between molecules are much... Than the forces among formula...

Weaker than the forces among formula units in ionic bonding

33

This difference in the strength of attraction between the basic units of molecular and ionic compounds gives rise to

Different properties in the two types or compounds

34

The melting pt, boiling pt, and harness of a compound depend on how

Strongly it's basic units are attracted to each other

35

Because the forces of attraction between individual molecules are not very strong many molecular compounds melt at

Low temperatures

36

Many molecular compounds are completely.... At room temperature

Gaseous

37

The ions in ionic compounds are held together by strong attractive forced do ionic compounds generally have higher

Melting and boiling points than do molecular compounds

38

Ionic compounds are hard but

Brittle

39

In an ionic crystal even a slight shift of one town of ions relative to another causes a large

Buildup of repulsive forces

40

These repulsive forces in the ionic crystals make it difficult for one layer to move

Relative to another, causing ionic compounds to be hard

41

If one layer is moved, however, the repulsive forces make the layers part

Completely, causing ionic compounds to be brittle

42

In the solid state, ions cannot move, so the compounds are not

Electrical conductors

43

In the solid state, ions cannot move, so the compounds are not

Electrical conductors

44

In the molten state, ionic compounds are electrical conductors because the ions can move

Freely to carry electrical current

45

Many ionic compounds can...in water

Dissolve

46

When ionic compounds dissolve their ions separate from each other and become

Surrounded by water molecules

47

These ions are free to move through the solution so sucks solutions are

Electrical conductors

48

Other ionic compounds do not dissolve in water, however, because the attractions between the water molecules and the ions cannot overcome the

Attraction. Between the ions

49

Certain aims bond covalently with each other to form a group of atoms that has both

Molecular and ionic characteristics

50

A poly atomic ion is a charged group of

Covalently bonded atoms

51

Poly atomic ions combine with ions of opposite charge to form

Ionic compounds

52

The charge of a poly atomic ion results from an excess of

Electrons (negative charge) or a shortage of electrons (positive charge)

53

If the ion is negatively charged add to the total number of cal me electrons a number of electrons corresponding to the

Ions negative charge

54

If the ion is positively charged, subtract from the total number of valence electrons s number of the electrons corresponding not to the ions

Positive charge