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Flashcards in Chemistry 1 Deck (38):
1

What is meant by compound

substances in which atoms of two or
more elements are chemically combined.

2

Chemical bonding involves what

either transferring or sharing electrons in the highest occupied energy levels (shells) of atoms

3

Why are electrons shared or transferred in chemical bonding

So that the compound has the electronic structure of a noble gas ( full outer shell )

4

When atoms form chemical bonds by transferring electrons this is called a

ionic bond

5

Atoms that lose electrons become

positively charged ions

6

Atoms that gain electrons become

negatively charged ions

7

Ions should have the electronic structure of which periodic group

0 ( noble gases )

8

Elements from group 7 ( halogens ) react with which elements to form ionic compounds

All the alkali metals

9

An ionic compound can be described as what ( in the context of size )

giant structure

10

Ionic compounds are held together by what

Strong electrostatic forces of attraction between oppositely charged ions

11

Ionic compounds have what form

Lattice

12

When atoms form chemical bond by sharing electrons this is called

covalent bond

13

Are covalent bonds strong or weak

Strong

14

Metal molecules consist of what type of structure

Giant structures of atoms arranged in a regular pattern

15

Electrons is the highest energy level are...

delocalised

16

Delocalised means

Free to move through the whole structure

17

Substances that consist of simple molecules have relatively high or low melting and boiling points

low

18

Why do ionic compounds have high melting points

Lots of energy is required to break the many strong bonds

19

Why is it that when ionic compounds are melted they can conduct electricity

The ions are free to move and carry the current

20

Macromolecules, or giant structures can form from what

Atoms that share electrons ( covalent bonding )

21

How many covalent bonds of each carbon atom form diamond

4

22

What size is diamonds structure

massive

23

How many covalent bonds of each carbon carbon atom forms graphite

3

24

What is the structure of graphite and what is the nature of these layers

Layers which slide over each other

25

Why do the layers in graphite slide over each other

Because there are no covalent bonds between the layers meaning there is weak force causing this slipperiness

26

Why can graphite conduct heat and electricity

Because each atom has one delocalised electron

27

What can fullerenes be used for

drug delivery in the body, in lubricants and for catalysts

28

What can nanotubes be used for

reinforcing materials such as tennis rackets

29

Why can metals conduct electricity and heat

Because of the delocalised electrons in their structures

30

Why can metals be bent and shaped

Because the layers of atoms in metals are able to slide over each other

31

Alloys are made from what

two or more different metals

32

Why does making an alloy make the substance harder

Because different sized atoms of metals distort the layers in the structure making it more difficult for them to slide over each other

33

What do shape memory allows do after being deformed and name an example

Return to their original shape, Nitinol used in dental braces

34

What defines the properties of a polymer

What they are made from and the conditions under which they are made

35

Thermosoftening polymers consist of

Individual tangled polymer chains

36

Thermosetting polymers consist of

polymer chains with cross-links between them so they do not melt when heated

37

Nanoscience refers to structures that are

1-100nm in size

38

Is it thermosetting or softening that can be melted easiliy

thermosoftening