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WJEC GCSE Chemistry 1 > Substances And Chemical Reactions > Flashcards

Flashcards in Substances And Chemical Reactions Deck (97)
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1

How can each element also be written?

As a unique chemical symbol

2

What is an element made up of?

Atoms (all of the same type)

3

What is at the centre of every atom?

A nucleus

4

What charge does a nucleus have?

Positive

5

What particles are found in the nucleus?

Protons

Neutrons

6

What charge do protons have?

Positive

7

What charge do neutrons have?

Neutral

8

What particles surround the nucleus?

Electrons

9

What charge do electrons have?

Negative

10

Why does the electrons surround the nucleus?

They are attracted to it

11

Why are electrons attracted to the nucleus?

Positive (protons in the nucleus) attracts negative (electrons)

12

What does every atom of a particular element have the sam number of?

Protons

13

How is the number of protons indicated on a periodic table?

The atomic number (the smaller number at the bottom of the symbol)

14

If the number of protons of an element is always the same, what else can be said?

The atomic number is always the same

15

What is the atomic number of hydrogen (this can be looked up in the periodic table)?

1

16

What is the atomic number of lithium (this can be looked up in the periodic table)?

3

17

What is the atomic number of chlorine (this can be looked up in the periodic table)?

17

18

How is the mass of an atom recorded?

Relative atomic mass (a unit-less measurement)

19

What mass does a proton have?

1

20

What mass does an electron have?

Negligible (it is so small we don’t count it)

21

What mass does a neutron have?

1

22

Essentially what is relative atomic mass?

Essentially the number of protons + number of neutrons

23

How can the number of neutrons be worked out from an atoms relative atomic mass?

Take the atomic number (number of protons) away from the relative atomic mass

i.e. (protons + neutrons - protons = neutrons)

24

What chemists sorted all of the known elements into?

The Periodic Table

25

What do all chemicals have as a short hand for writing them?

Symbols (for elements) or formulae (for molecules)

26

How many letters does a chemical symbol have?

1 or 2

27

Are all chemical symbols obviously related to the name of the element which they represent?

No!

28

What is the chemical symbol for lead?

Pb

29

What is the chemical symbol for mercury ?

Hg

30

What is the chemical symbol for tin?

Sn