Atom Structure and Mass

Question 1

What is the basic unit of matter?

Answer 1

Atom

Question 2

What are the three primary subatomic particles of an atom?

Answer 2

Protons, neutrons, and electrons

Question 3

True or False: Protons have a negative charge.

Answer 3

False

Question 4

What is the charge of a neutron?

Answer 4

Neutral

Question 5

What is the mass of a proton approximately in atomic mass units (amu)?

Answer 5

1 amu

Question 6

Fill in the blank: The nucleus of an atom contains ______ and ______.

Answer 6

Protons; neutrons

Question 7

What is the relative atomic mass of an element?

Answer 7

The weighted average mass of an atom of an element compared to 1/12 of carbon-12

Question 8

Which subatomic particle determines the chemical identity of an element?

Answer 8

Proton

Question 9

What is mass spectrometry used for?

Answer 9

To measure the mass-to-charge ratio of ions

Question 10

True or False: Mass spectrometry can identify the isotopic composition of an element.

Answer 10

True

Question 11

What does relative isotopic abundance refer to?

Answer 11

The percentage of a particular isotope of an element in a sample

Question 12

Which particle has a mass that is negligible compared to protons and neutrons?

Answer 12

Electron

Question 13

What is the formula to calculate the relative atomic mass from isotopic abundances?

Answer 13

Σ(isotopic mass × relative abundance)

Question 14

Fill in the blank: Isotopes of an element have the same number of ______ but different numbers of ______.

Answer 14

Protons; neutrons

Question 15

What is the primary purpose of a mass spectrometer?

Answer 15

To separate ions based on their mass-to-charge ratio

Question 16

What is the typical unit of measurement for relative atomic mass?

Answer 16

Atomic mass unit (amu)

Question 17

True or False: The relative atomic mass of an element is always a whole number.

Answer 17

False

Question 18

What does the term ‘isotopic mass’ refer to?

Answer 18

The mass of a specific isotope of an element

Question 19

What instrument is used to perform mass spectrometry?

Answer 19

Mass spectrometer

Question 20

What happens to ions in a mass spectrometer after they are formed?

Answer 20

They are accelerated and then separated based on their mass-to-charge ratio

Question 21

Fill in the blank: The abundance of isotopes is often expressed as a ______.

Answer 21

Percentage

Question 22

True or False: The number of neutrons in an atom can vary, resulting in different isotopes.

Answer 22

True

Question 23

What is the significance of carbon-12 in relative atomic mass?

Answer 23

It is the standard for defining atomic mass units.

Question 24

What is the term for the average mass of an element’s isotopes weighted by their natural abundance?

Answer 24

Weighted average atomic mass

Question 25

Which type of ion is produced in a mass spectrometer?

Answer 25

Charged ions

Question 26

What is the effect of an isotope on the relative atomic mass of an element?

Answer 26

It contributes to the weighted average depending on its abundance.

Question 27

Fill in the blank: Mass spectrometry can also be used to determine ______ of compounds.

Answer 27

Molecular weight

Question 28

True or False: All elements have only one stable isotope.

Answer 28

False

Question 29

What does a mass spectrum display?

Answer 29

The abundance of ions as a function of their mass-to-charge ratio

Question 30

What is the relationship between the number of protons and the atomic number?

Answer 30

The atomic number is equal to the number of protons.

Question 31

What can mass spectrometry reveal about a sample?

Answer 31

Its composition and structure

Question 32

Fill in the blank: The mass of an electron is approximately ______ times less than that of a proton.

Answer 32

1836

Question 33

What is the role of the detector in a mass spectrometer?

Answer 33

To detect and quantify the ions after separation

Question 34

True or False: Isotopes of an element have identical chemical properties.

Answer 34

True

Question 35

What does the term 'ionization' refer to in mass spectrometry?

Answer 35

The process of converting atoms or molecules into ions

Question 36

Fill in the blank: The ______ of an atom is determined by the number of protons in its nucleus.

Answer 36

Element

Question 37

What is the significance of isotopic analysis in mass spectrometry?

Answer 37

It helps in understanding elemental composition and tracing sources.

Question 38

What is the formula for calculating the average atomic mass from multiple isotopes?

Answer 38

Σ(isotopic mass × fractional abundance)

Question 39

True or False: The relative atomic mass is influenced by the presence of isotopes.

Answer 39

True

Question 40

What is the main advantage of using mass spectrometry in chemistry?

Answer 40

High sensitivity and accuracy in measuring masses.