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Flashcards in Physical Abd Chemical Changes Deck (21):
1

Chemical property

A substances ability to react with other substances to form new products

2

Chemical change

A change in nature of the starting materials undergoing a chemical reaction to produce one or more new substances difficult to reverse

3

Reactant

Starting materials is chemical reaction

4

Product

stuff that is made in chemical reaction

Reactant -> product ( which can be more than 1

5

5 signs of chemical reaction

Temperature change
Colour change
Odour produced
Solid produced precipitate
Gas or bubbles
New substance formed

6

First elements were proposed by

Alchemists ( Europe)

7

First elements were

Air fire water earth

8

What was the alchemists purpose

To change metal / lead to gold

9

What is matter made of

Atoms

10

What are elements made of

Atoms

11

Atomic theory

All matter is made of small particles called atoms atoms can’t be created or destroyed or minimized same element same mass all element atoms mass differ compounds are created when atoms of different atoms link together in definite proportions

12

JJ Thomson

Discovered electrons and used a cathode to discover them used the plum pudding model

13

Ernest Ruth ford

Discovered protons used gold foil experiment to discover proton proposed nuclear model

14

Ruth fords conclusion I

The atom is mostly empty space with a solid positive center called a nucleus

15

Niels Bohr

Proposed electrons occupied energy levels called shells or orbitals

16

What is an atom made up of

Subatomic particles

17

How many subatomic particles are there

Name them

3

Protons neutrons electrons

18

Protons

Symbol - p
Mass- 1 electric charge (+)

Location - nucleus

19

Neutrons

Symbol-n
Mass- slightly more than 1
Electric charge - o
Location- nucleus

20

Electrons

Symbol- e
Mass - so small almost 0
Electric charge (-)
Location- in shells around nucleus

21

Kinetic energy

energy that a body possesses by virtue of being in motion