The Atom

Question 1

Subtract atomic number from atomic mass to find the number of ________.

Accepted Answer

neutrons

Question 2

An elelment has an atomic number of 51 and mass of 121. How many neutrons does it have?

Accepted Answer

70

Question 3

The positively charged subatomic particle in the nucleus

Accepted Answer

proton

Question 4

What is used to identify a particular element?

Accepted Answer

The number of protons

Question 5

The Modern Atomic Theory proposes that electrons travel in ______________.

Accepted Answer

a cloud

Question 6

Most of weight of an atom is located in the________________.

Accepted Answer

neucleus

Question 7

All matter is made of ________________.

Accepted Answer

atoms

Question 8

Which substance is a compound: He, Si, Fe, CO

Accepted Answer

CO

Question 9

Atoms are mostly _____________ space.

Accepted Answer

empty

Question 10

Which scientist discovered electrons and has a plum-pudding model of an atom.

Accepted Answer

J.J. Thomson

Question 11

The nucleus of an atom is made up of __________.

Accepted Answer

neutrons and protons

Question 12

Carbon has 6 protons. How many electrons does it have?

Accepted Answer

6

Question 13

The neutron has _____charge

Accepted Answer

a neutral

Question 14

The ____________ _________will tell you the number of protons in an atom.

Accepted Answer

atomic number

Question 15

The negatively charged subatomic particle is the

Accepted Answer

electron

Question 16

What scientist was the first to propose that elements can join to make new substances.

Accepted Answer

John Dalton

Question 17

Which scientist proposed that electrons follow set paths around the nucleus .

Accepted Answer

Neils Bohr

Question 18

Democritus said that the atom was made of a single substance that is _______________

Accepted Answer

uncuttable

Questions 18