Chemistry 9

Question 1

Atomic theory by John Dalton?

Answer 1

Matter is composed from atoms, identical in mass and size of other elements

Question 2

Atomic theory by J.J Thompson?

Answer 2

Raisin bun model:

Charged bun positive

Raisins negative, eventually found out its called electrons

Question 3

Atomic theory from Ernest Rutherford?

Answer 3

Dense center called nucleus and electrons moved around it

Question 4

Atomic theory of Neils Bohr?

Answer 4

Electrons surrounding the nucleus in energy levels or shells

Question 5

What makes up most of size of an atom?

Answer 5

The valence shell and electrons

Question 6

What makes up most of mass of an atom?

Answer 6

Protons and neutrons

Question 7

What are the horizontal rows in the periodic table called?

Answer 7

Periods

Question 8

What are the vertical columns in the periodic table called?

Answer 8

Families

Question 9

Name each families in the periodic table, their charge and if it loses or gains electrons

Answer 9

Alkali metals, + , loses electron

Alkali earth metals, 2+ , loses 2 electrons

Halogens, - , gains electron

Noble gases, neutral, neutral

Question 10

Differences between Metals and Non metals

Answer 10

Metals: give away electrons to form positive ions, conductors

Non metals: gain electrons to form negative ions, inductors

Question 11

What are metalloids and where are they found in the periodic table

Answer 11

Metalloids are both metal and non metal and found around the staircase

Question 12

Difference between chemical change and physical change

Answer 12

Chemical change: new compounds formula made from heat

Physical change, changes of state

Question 13

Two chemical bonds and how are they formed?

Answer 13

Ionic bond: metal to non metal

Covalent bond: non metal to nonmetal

Question 14

What is a chemical reaction

Answer 14

When the chemicals react to form new elements