Module Two - Atoms, Elements, Molecules, and Ions

Question 1

Where do you find the atomic number and where do you find the mass number?

Answer 1

Atomic number is the number on the bottom and the mass number on the top.

Question 2

What is the atomic number?

Answer 2

The number of protons.

Question 3

What is the mass number?

Answer 3

The number of protons plus neutrons.

Question 4

What is an isotope?

Answer 4

A different form of an element that contains the same number of protons but a different number of neutrons.

Question 5

When passed through electrically charged plates, what kind of radiation is reflected and what is not?

Answer 5

Alpha and beta are reflected, whereas gamma is not.

Question 6

What is an electron?

Answer 6

A subatomic, negatively charged particle.

Question 7

What are ions?

Answer 7

Charged atoms or groups of atoms.

Question 8

What is a proton?

Answer 8

Fundamental, positively charged components of atomic structure.

Question 9

What does the “plum pudding” model suggest?

Answer 9

All alpha particles should pass directly through atoms, undeflected. This was based on the fact that like charges repel, opposites attract, and electons are embedded in a sea of positive stuff.

Question 10

What did Rutherford’s model of the atom suggest?

Answer 10

A tiny number of the alpha particles should be deflected by the positively charged nucleus.

Question 11

What are anions and cations?

Answer 11

They are both ions, but cations are positively charged and have more protons than electrons, and anions are negatively charged and have more electrons than protons.

Question 12

What happened to the particles in Rutherford’s experiment?

Answer 12

Most passed through undeflected, but some were deflected at large angles, and other were reflected back to the source.

Question 13

How much bigger is an atom than its nucleus?

Answer 13

20,000x bigger!

Question 14

How do you measure average atomic mass?

Answer 14

Take the weights of each isotope in AMU and multiply them by their ratio.

(6.015 * .0742 + 7.016 * .9258 = 6.942u)

Question 15

What does multiple peaks in a mass spectrometry graph tell us?

Answer 15

Not all atoms of the same element will have the same mass! Each peak corresponds to a different mass.

Question 16

What is a mass spectrometer?

Answer 16

An instrument that measures the mass-to-charge ratio of atoms or molecules.

Question 17

Elements along a column in the periodic table share…

Answer 17

Chemical characteristics.

Question 18

What are the 7 diatomic elements?

Answer 18

H2, N2, O2, F2, CL2, Br2, and I2.

Question 19

What is a monatomic ion?

Answer 19

A single atom that has gained or lost electrons.

Question 20

Metals _ electrons, so their ions are _ charged.

Answer 20

Metals lose electrons, so metal ions are positively charged.

Question 21

Non-metals _ electrons, so their ions are _ charged.

Answer 21

Non-metals gain electrons, so their ions are negatively charged.

Question 22

Why does hydrogen appear twice on the periodic table?

Answer 22

Because it can lose or gain an electron.

Question 23

Negative charges for groups 5A, 6A and 7A are…

Answer 23

8 MINUS that groups number.

So, 6A negative charge would be 8-6 = -2.

Question 24

Positive charges for groups 1A and 2A are…

Answer 24

equal to the group number! So 1A positive charge is 1.

Question 25

Positive charges for 3A equals…

Answer 25

it’s group number, so, 3.

Question 26

Transition metals can lose verying numbers of electrons, which means most transition metals…

Answer 26

can for 2+ ions, with many able to form 3+ ions too!

Question 27

Ionic compounds are neutral, which means they have…

Answer 27

no net charge.

Question 28

When writing names for ionic compounds, how do you name a compound that has a metal that can form only one type of cation?

Answer 28

Use the name of the metal, for example, potassium oxide.

Question 29

What metals form more than one kind of cation?

Answer 29

Cr, Cu, Co, Fe, Pb, Hg, or Sn. We indicate the kind of cation using roman numerals. (such as iron(II) chloride).

Question 30

What is an ionic compound?

Answer 30

A compound who consists of positive and negative ions.

Question 31

When do ionic compounds form?

Answer 31

When metal react with nonmetals. Metal atoms removed relatively easily to form positive cations.

Question 32

What is a polyatomic ion?

Answer 32

A unit of two or more atoms that bears a net electrical charge.

Question 33

What are molecular compounds?

Answer 33

Covalent bonds formed by the sharing of electrons between two or more non-metals.

Question 34

How do you name a binary molecular compound?

Answer 34

Name the elements in order, with prefixes showing the number of each atom present and the second element ending in -ide, for example, dinitrogen tetrafluoride.

Question 35

What is a salt?

Answer 35

A metal + a nonmetal, so, an ionic compound. The metal donates electrons that the nonmetal accepts.

Question 36

In Coulomb’s Law for Energy, U stands for…

Answer 36

potential energy.

Question 37

In Coulomb’s law, the magnitude of U increases with…

Answer 37

more charging and a smaller separation.

Question 38

In Coulomb’s law, U < 0 is _ while a U > 0 is _.

Answer 38

U < 0 is attractive and a U > 0 is repulsive. A stronger ionic bond represents a greater magnitude of U.