Ch 2 Part 1 Atoms

Question 1

Postulate 1

Answer 1

All matter is made up of tiny particles called atoms

Smallest particle of an element that retain the chemical properties of the element

The interaction among elements accounts for the property of matter

Question 2

Postulate 2

Answer 2

All atoms of a given element have the same chemical properties

Atoms of different elements have different chemical properties

Question 3

Postulate 3

Answer 3

In ordinary chemical reactions, no atom of any element disappears or is changed into an atom of another element

Question 4

Postulate 4

Answer 4

Compounds are formed by the chemical combination of 2 or more different kinds of atoms

Number of atoms in an element are constant and are commonly expressed as integers

Question 5

Postulate 5

Answer 5

A molecule is a tightly bound combination of 2 or more atoms that act as a single unit

Question 6

Law of Conservation of Mass

Answer 6

Matter can neither be created nor destroyed

No change in mass in an ordinary chemical reaction

Question 7

Monatomic

Answer 7

Elements that consist of single atoms that are not connected to each other

Question 8

Diatomic elements

Answer 8

2 atoms in each molecule, connected to each other by a chemical bond

Ex: halogens

Oxygen O2

Question 9

Halogens

Answer 9

Oxygen O2
Hydrogen H2
Nitrogen N2
Fluorine F2
Chlorine C2
Bromine Br2
Iodine I2

Question 10

Proton

Answer 10

Positive charge

Question 11

Neutron

Answer 11

In nucleus
No charge

Question 12

Electron

Answer 12

Outside nucleus
Negative charge

Question 13

How do you find mass number?

Answer 13

Protons + neutrons

Question 14

Atomic #

Answer 14

Number of protons in the nucleus of an element
Above the symbol

Question 15

Atomic Mass

Answer 15

Average of the masses of all isotopes of an element

Question 16

Isotopes

Answer 16

Atoms with the same number of protons but different number of neutrons

Question 17

Metals

Answer 17

Solid at room temp (except mercury)
Shiny, conductors of electricity
Malleable
Give up electrons in reactions
Alloys-multiple metals combined together

Ex: Brass (copper and zinc)

Question 18

Nonmetals

Answer 18

18 on right side of period table (hydrogen on left )
Do not conduct electricity (expect graphite)
In reaction-accept electrons
Virtually all compounds built from H,C,N,O,P and S

Iodine /phosphorus solid
Bromine liquid
Helium to radon gases (noble gases)

Question 19

Metalloids

Answer 19

6 elements
Boron, silicone, germanium, arsenic, antimony, tellurium

Shiny but do not conduct electricity