ch2

Question 1

Antonio Lavoisier law of..

Answer 1

law of consecration of mass:
that mass is neither created nor destroyed
- mass of product must = the mass of reactants.

Question 2

Joseph prost law of

Answer 2

low of definite proportions.

a given compound always contains exactly the same proportions of element by mass.

Question 3

John dalton law of..

Answer 3

law of multiple proportions

different proportions mean different compound

Question 4

John Dalton proposed explanations for the laws of mass conservation, definite & multiple proportions:

Answer 4

• all elements is composed of tiny particles called atoms
• chemical reactions only rearrange the way of atoms combine, but dont change the atom themselves
• all atoms of a given element are the same and atoms of different elements are different
• compound always have the same type and number of atoms

Question 5

to Characterize the Atom: Electron we use..

Answer 5

• cathode ray tube by J.J Thomson
• concluded that
• electrons contain negative charge
• measured the charge/mass

Question 6

thomson atomic model

Answer 6

like a “plum pudding”.

Question 7

Robert Millikan

Answer 7

*experiment Electron Charge by using (charged oil drops)

• concluded
• charge/mass
• electron charge
• electron mass

Question 8

Rutherford’s Atomic Model

Answer 8

• discovered 3 different types of radioactivity: a, b, g
• elpha have the bigger mass
• discoverd the nuclear atom

-Gamma rays (γ)
High-energy light

-Beta particles ()
High-speed electrons

-Alpha particles (α)
Particles with 2+ charge
has bigger mass

Question 9

The Gold Foil Experiment of rather

Answer 9

• used the alpha particles in a experiment with the discovery of the “nuclear atom”
• used radioactivity beam of alpha particles, in a lead block container
• he used gold because it have simple less atoms
• used a screen to show the elpha particles when it will het it

Question 10

how Rutherford experiment went and it results

Answer 10

most particles went through straight the gold

some particles where deflected

few particles rebounded

which make us conclude that some atoms contain nuclear which have different charge, that made the elpha particles rebound

Question 11

ratherfords nuclear model

Answer 11

atoms have nuclear with contain (positive charge) protons and (no charge )neutrons

Question 12

electrons, protons and neutrons (charge and mass)

Answer 12

Electrons have less mass
-We ignore sometimes the mass of the electrons due its so few mass
-Protons and nuetrons have the mass
-Electrons = protons charge but with oppisite charge
-Mass of atoms= P+N
(JUST IN THE NUCLIEC ATOMS)

Question 13

nucleus contain

Answer 13

protons and neutrons

Question 14

Protons:

Answer 14

Have a positive charge that is equal in magnitude to the electron’s negative charge

Question 15

Neutrons:

Answer 15

Have virtually the same mass as a proton but no charge

Question 16

what is

• atomic mass
• mass number
• atomic mass

Answer 16

• atomic mass: number of protons
• mass number: total number of protons and neutrons in an atom
• atomic mass: mass of an atom, measured in grams or amu(atomic mass unit)

Question 17

an ion is

Answer 17

is an atom, or group of atoms, that has a net positive or negative charge.

Question 18

types of ion and what are they

Answer 18

cation: positive charge, loss charge
anion: negative charge, gain charge

Question 19

A monatomic ion is..

A polyatomic ion ..

Answer 19

A monatomic ion contains only one atom

A polyatomic ion contains more than one atom

Question 20

Are Elements in the vertical columns with similar chemical properties ?

Answer 20

yes

Question 21

group 1 - group 2 - G7 - G8 names

Answer 21

G1: alkali metals (very active element)
G2: alkaline earth metals
G7: Halogen non-metals
G8: noblegases non-metales (little chemical reactivity)

Question 22

Covalent Bonds

Answer 22

Bonds are forces between atoms by sharing electrons.

Resulting collection of atoms is called a molecule.

Question 23

what is diatomic molecule and poly Tomic molecule

Answer 23

• A diatomic molecule contains only two atoms

* A polyatomic molecule contains more than two atoms

Question 24

Ionic Bonds

Answer 24

Bonds form due to force of attraction between oppositely charged ions.

Ion – atom or group of atoms that has a net positive or negative charge.

Cation – positive ion; lost electron(s).

Anion – negative ion; gained electron(s).

Question 25

Oxyanions

Answer 25

Anions(-) that contain an atom of a given element and different numbers of O atoms

Question 26

acid

Answer 26

An acid is a molecule with one or more H+ attached to an anion(-)

Acids can be recognized by the hydrogen that appears first in the formula—HCl.