Topic 1 - (periodic table and elements and compounds) Flashcards Preview

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Flashcards in Topic 1 - (periodic table and elements and compounds) Deck (24)
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1

What are the 2 types of molecules?

Elements and compounds

2

What is an element?

More than 2 of the same atom or molecule

3

What is a compound?

More than 2 different elements chemically combined

4

Are compounds pure substances or mixtures?

Pure substances

5

What is a mixture?

2 or more different substances not chemically combined

6

Miscible

Can mix

7

Imiscible

Cannot mix

8

Why does distillation work?

because the substances have different boiling points, so the substances with the lowest boiling points will evaporate first

9

What is group 1 on the period table?

Alkali metals

10

What is group 7 on the periodic table?

Halogens

11

What is group 0/8 on the periodic table?

Noble gases

12

As you go down group 1 (alkali metals) ...

- They get MORE reactive
- the atomic number increases
- the melting and boiling point DECREASES

13

As you go down group 7 (halogens)..

- they get LESS reactive
- the atomic number increases
- the melting and boiling point INCREASES

14

The Noble gases Group 0/8 ...

-colourless
- unreactive

15

Why are the noble gases unreactive?

Because they have a full outer shell of 8 electrons

16

What are most of the elements on the periodic table?

METALS

17

What side are metals and non-metals on the periodic table?

Metals on the LEFT
Non-metals on the RIGHT

18

Some properties of metals are....

- conduct heat and electricity
- sonorous
- malleable
- ductile

19

Some properties of non-metals are....

- do NOT conduct heat or electricity
- are NOT malleable
-are NOT ductile
- are NOT sonorous

20

Do metals or non-metals have higher densities?

METALS

21

What is the difference between a compound and a mixture?

A compound has 2 or more different elements chemically combined

WHEREAS

A mixture has 2 or more different substances (elements or compounds) NOT chemically combined

22

What are some properties of group 1 alkali metals?

- can be easily cut with a knife
- low densities
- some float on water

22

What are the halogens?

Non - metals

23

What is a molecule?

2 or more atoms chemically combined