Ch2 Atoms, Molecules & Ions

Question 1

Law of constant composition

Answer 1

each compound has the same kind and number of elements

Question 2

Low of conservation of mass

Answer 2

in chem RXN, the total mass before is equal after rxn.

Question 3

Law of multiple proportions

Answer 3

mass of B combined with A = ratio of small whole numbers

when A & B make more than 1 compound

Question 4

Atoms are electrically…

Answer 4

Neutral

Question 5

or protons =

Answer 5

of electrons

Question 6

Ion

Answer 6

charged atom/ group of atoms

Question 7

Ionic Bonds

Answer 7

electrical attraction amongst charged ions (strong bond)

Question 8

P. Table group 1

Answer 8

Alkali metal (1+ charge)

Question 9

Group 2

Answer 9

Alkaline earth metals (2+ charge)

Question 10

Group 3

Answer 10

3+ charge for Al & B only

Question 11

Group 6

Answer 11

Oxygen family 2- charge Oxide/ sulphide

Question 12

Group 7

Answer 12

Halogens (1- charge) drop ‘ine’ and add’ ide’

Question 13

Group 8

Answer 13

Noble Gases - full valence shell and No Ionic formation

Question 14

Covalent Bonding

Answer 14

electron sharing (weaker attraction)
- organic substances like wood, skin / hair

Question 15

Metalic Bonds

Answer 15

Share AND transfer of electrons

- STRONGEST BOND (Metals & alloys)

Question 16

Model of Atom

Answer 16

• positive charge in center, e- in orbit
• p+ & N in nucleus = atomic mass
• e- are responsible for atoms volume

Question 17

Angstrom

Answer 17

non- SI unit to denote atomic length

1/10 of a Nanometer

Question 18

Atomic Number

Answer 18

no. of p+ in nucleus

Question 19

Mass Number

Answer 19

No. of p+ and N in nucleus

- Isotopes have same p+ but different mass # due to more neutrons

Question 20

Isotope

Answer 20

different number of neutrons

Question 21

Atomic mass units

Answer 21

Used to measure small masses of individual atoms

Question 22

Rows in periodic table —>

Answer 22

Periods

Question 23

Columns

Answer 23

Groups

Question 24

Metals location on P. Table

Answer 24

Left side

good conductors/ malleable / lustrous

Question 25

Nonmetals location

Answer 25

top right side

brittle/ dull / poor conductors

Question 26

Molecule structure

Answer 26

2+ atoms bound tightly together

Question 27

Molecule chemical formula

Answer 27

which atoms are present, and in what proportions (h2o)

Question 28

Emperical formulasn

Answer 28

give relative number and types of atoms in molecule (ratio considered)

Question 29

Positively charged Ion

Answer 29

Cations (metals in general)

Question 30

Negatively charged Ions

Answer 30

Anions ((generally nonmetals)