Chemistry

Question 1

Matter

Answer 1

A physical substance

Question 2

Atom

Answer 2

Building blocks of matter

Question 3

Element

Answer 3

Pure substance that cannot be separated into simpler substance by physical or chemical means

Question 4

Molecules

Answer 4

two or more atoms joined together.
Same = element
different = compounds

Question 5

Compounds

Answer 5

two different elements chemically bonded can only separated chemically

Question 6

Mixture

Answer 6

two or more substances that are physically combined

Question 7

John Dalton atom theory

Answer 7

He believed that elements were made up of atoms. Atoms cannot be divided or destroyed.

Question 8

JJ Thompson atom theory

Answer 8

Suggested that electrons float in a blob of positive charge (plum pudding)

Question 9

Rutherford atom theory

Answer 9

Atoms are mainly empty space
Some deflected meaning the nucleus was positively charged

Question 10

Niel Bohr atom theory

Answer 10

believed that the electrons orbited the nucleus in shells

Question 11

Describe reactivity of elements in the periodic table

Answer 11

Reactivity is increased when an element needs to lose or gain one or two electrons to have a full outer shell. The further away electrons are from the nucleus the weaker the connection is.

Question 12

What is the difference between rust and corrosion

Answer 12

Corrosion is the result of a chemical reaction.
Rust is accelerated by certain chemicals

Question 13

John Dalton periodic table development

Answer 13

Only 20 elements weren’t ordered a specific way

Question 14

Johan Wolfgang Doblener periodic table development

Answer 14

Arranged in the increasing of atomic mass in triads
atomic weight of the middle element is equal to the average of the 2 end elements. 32 elements

Question 15

John Newlands periodic table development

Answer 15

56 elements arranged in rows and columns by atomic weight

Question 16

Demirtri Mendeleev

Answer 16

Our Periodic table today arranhged by increase of atomic masses.
8 groups he left spots for undiscorvered elements

Question 17

What is an Isotope

Answer 17

Elements that have same number of protons by different number of neutrons

Question 18

What is a radioisotope

Answer 18

Have an unstable nucleus which will decay to have a more stable nucleus

Question 19

Different types of radioactive decay

Answer 19

Alpha, Beta, Gamma

Question 20

Composition, blocked and effect of an Alpha particle

Answer 20

2 Protons 2 Neutrons
Paper and 6cm of air
High

Question 21

Composition, blocked and effect of an Beta particle

Answer 21

Fast moving electron
Plastic
Medium

Question 22

Composition, blocked and effect of an Gamma particle

Answer 22

Electromagnetic wave
Lead shielding
Low

Question 23

What is a half-life

Answer 23

The time it takes for half the atoms to decay