Atomic structure and isotopes - 2.1 - (1)

Question 1

What does the atom consist of?

Answer 1

a nucleus made up of two types of subatomic particles = protons and neutrons

Question 2

What is the third type of subatomic particle?

Answer 2

an electron which occupies a region outside the nucleus

Question 3

How are electrons arranged?

Answer 3

around the nucleus in shells

Question 4

What kind of masses do atoms and their subatomic particles have?

Answer 4

tiny masses

Question 5

What do chemists use instead of working in grams?

Answer 5

they compare the masses of subatomic particles using relative masses

Question 6

What virtually has the same mass as a neutron?

Answer 6

proton

Question 7

What is the negligible mass of an electron?

Answer 7

1/1836th the mass of a proton

Question 8

What do accurate measurements show?

Answer 8

a neutron has a slightly greater mass than a proton

Question 9

By which factor is a neutron slightly greater than a proton?

Answer 9

1.001375

Question 10

What do chemists assume after they see that neutrons have a slightly greater mass than protons by the factor suggested?

Answer 10

this is close to 1 that chemists usually assume that protons and neutrons have the same mass

Question 11

What type of subatomic particle has a positive charge?

Answer 11

proton

Question 12

What type of subatomic particle has a negative charge?

Answer 12

electron

Question 13

The charge on a proton…

Answer 13

is equal but opposite to the charge on an electron - the charges balance

Question 14

What type of subatomic particle has no charge?

Answer 14

neutron

Question 15

What is the actual charge on a single proton that is tiny?

Answer 15

+1.60217733 x 10^-19C

Question 16

What is a much easier way instead of using actual charges?

Answer 16

relative charges

Question 17

What is the relative charge for a proton?

Answer 17

1+

Question 18

What is the relative charge for an electron?

Answer 18

1-

Question 19

Nearly all of an atom’s…

Answer 19

mass is in the nucleus

Question 20

What do atoms contain the same number of?

Answer 20

protons and electrons

Question 21

What is cancelled by the total negative charge from electrons?

Answer 21

the total positive charge from protons

Question 22

What is the overall charge of an atom?

Answer 22

zero

Question 23

Is an atom neutral?

Answer 23

yes

Question 24

What are neutrons thought to be as for the nucleus?

Answer 24

as a glue that holds the nucleus together despite the electrostatic repulsion between its positively charged protons

Question 25

Most atoms contain the same number of, or slightly more,…

Answer 25

neutrons than protons

Question 26

What is needed as the nucleus gets larger?

Answer 26

more and more neutrons

Question 27

What identfies an element?

Answer 27

the number of protons in an atom

Question 28

As of 2014, the existence of how many elements has been confirmed?

Answer 28

114 elements

Question 29

Every atom of the…

Answer 29

same element contains the same number of protons

Question 30

Different elements contain atoms…

Answer 30

that have different numbers of protons

Question 31

The periodic table lists elements in order of the…

Answer 31

number of protons in the nucleus

Question 32

Each element is shown with the number of…

Answer 32

protons as its atomic number (or number of protons)