Chapter 4.1-4.3 Atomic Structure (HS Chemistry)

Question 1

Who gave us the first modern atomic theory but incorrectly thought the atom was indivisible?

Accepted Answer

John Dalton

Question 2

Which subatomic particle, if counted, uniquely identifies which element an atom belongs to?

Accepted Answer

protons

Question 3

Which subatomic particle(s) have equal but opposite charges, respectively +1 and -1 each?

Accepted Answer

protons and electrons

Question 4

What is the name of the isotope for 31P?

Accepted Answer

phosphorus-31

Question 5

Which two subatomic particles have the same relative mass of 1 amu?

Accepted Answer

proton and neutron

Question 6

What is the atomic number of an element equal to?

Accepted Answer

the number of protons only

Question 7

Which scientist confirmed the existence of the neutron?

Accepted Answer

James Chadwick

Question 8

Which scientist discovered the electron and proposed the plum pudding model of the atom?

Accepted Answer

JJ Thomson

Question 9

Why is the atomic mass of an element a decimal number and not a whole number? Because...

Accepted Answer

it is the weighted average mass of all natural isotopes

Question 10

Who used the “gold-foil experiments” to discover the nucleus of atoms?

Accepted Answer

Ernest Rutherford

Question 11

Which subatomic particle arrangement describes the chemical or physical properties of elements?

Accepted Answer

electrons

Question 12

Who first coined the term “atom” which means indivisible and indestructible?

Accepted Answer

Democritus

Question 13

Which scientist established the charge and mass of an electron?

Accepted Answer

Robert Millikan

Question 14

Who denied the existence of atoms because he didn't believe there could be "empty space"?

Accepted Answer

Aristotle

Question 15

Which subatomic particle(s) can be found in the nucleus?

Accepted Answer

protons and neutrons

Question 16

Which of the following conclusions did NOT result from Rutherford’s gold foil experiments?

Accepted Answer

The nucleus contains neutral particles called neutrons

Question 17

Which isotope of calcium is likely the most abundant?

Accepted Answer

calcium-40

Question 18

What is the mass number of an element equal to?

Accepted Answer

the number of protons + neutrons

Question 19

What are the number of protons, electrons and neutrons respectively in an atom of chlorine-35?

Accepted Answer

17 p+ , 17 e-, 18 n0

Question 20

Which of the following statements of Dalton’s atomic theory is entirely TRUE?

Accepted Answer

Atoms combine in whole number ratios to form compounds

Questions 20