4.3 Distinguishing Among Atoms

Question 1

elements are represented by ……………………….

Answer 1

atomic number, mass number , atomic mass

Question 2

Elements are different because they contain different numbers of ————-

Answer 2

protons (atomic number)

Question 3

Atomic number?

Answer 3

is the number of protons in the nucleus of an atom of that element

Question 4

The atomic number identifies————-

Answer 4

an element

Question 5

The number of Protons equals the number of————

Answer 5

Electrons

Question 6

Atoms are electrically neutral thus,

Answer 6

the number of electrons must equal the number of protons

Question 7

The Atomic number is———for the atom

Answer 7

unique

Question 8

The smaller number written on the element’s info is the———-

Answer 8

Atomic number (number of protons)

Question 9

Mass number?

Answer 9

The total number of protons and neutrons in an atom

Question 10

The bigger number in the element’s info is the————-

Answer 10

Mass number

Question 11

You can determine the atom’s composition by the———————————

Answer 11

atomic number and mass number

Question 12

Ex : gold-197 what is 197?

Answer 12

The mass number

Question 13

How can we find the number of neutrons?

Answer 13

Number of neutrons=mass number-atomic number

Question 14

The mass number is—————for the atom

Answer 14

Not unique

Question 15

A chemical symbol is a ————————

Answer 15

one- or two-letter abbreviation that represents a chemical element.

Question 16

The atomic number is the fundamental characteristic that defines an element’s identity(how?)

Answer 16

by telling if its oxygen , hydrogen , sodium etc. but the mass number when changed in oxygen for example it can be oxygen and ozone but most importantly both are oxygen

Question 17

Isotopes?

Answer 17

are atoms that have the same number of protons but different number of neutrons

Question 18

Because isotopes of an element have a different number of neutrons , they also have different———–

Answer 18

mass number

Question 19

Protons and electron are subatomic particles resposible for————

Answer 19

chemical behavior

Question 20

The number of neutrons in isotopes of an element dosent change———-

Answer 20

which element it is because the atomic number dosent change

Question 21

Atomic mass unit (amu)?

Answer 21

is defined as one twelfth of the mass of a carbon-12 atom (its a measuring unit)

Question 22

Atomic mass (Average atomic mass)?

Answer 22

The atomic mass of an element is the weighted average mass of the atoms in a naturally occurring sample of the element.

Question 23

The atomic mass is ————————-for the atom

Answer 23

not unique

Question 24

The Atomic mass is measured by a ———————-device.

Answer 24

spectrometer

Question 25

The unit of measurement for the atomic mass is--------

Answer 25

amu

Question 26

How is the average Atomic mass calculated?

Answer 26

Average atomic mass= (each isotope atomic mass * its percentage (abundance)) +(each isotope atomic mass * its percentage (abundance))

Question 27

Why do we calculate the Average atomic mass?

Answer 27

each element has its isotopes and each one of this isotope (element) is a mix of itself and some of another isotope, so we calculate how much of this mix with itself is abundant between all other isotopes so how much each isotope has this amount of for ex carbon-12 in carbon-13