Unit 5 Chemistry Practice Test Flashcards

Periodic table

The most useful source of general information about the elements for anyone associated with chemistry.

Dmitri Mendeleev

Who arranged the elements according to atomic mass and predicted properties of missing elements.

Noble gases

Elements that added a new column to Mendeleev's periodic table.

Arrangement by atomic number

A better arrangement than atomic mass for organizing elements in the periodic table.

Moseley's work

Showed that elements with similar properties occur at regular intervals when arranged by increasing atomic number.

Periodic law

States that the number of protons (atomic number) determines the position of each element in the periodic table.

Principal energy level

What each period in the periodic table corresponds to.

Alkaline-earth metals

Group to which calcium and magnesium belong (Group 2A).

Representative elements

Examples include Group 1A and 7A elements.

f orbitals

Characteristic orbitals of lanthanide elements.

Atomic number of sodium

11, which is the second element in Group 1A (after lithium).

Electron

The subatomic particle that reacts with other atoms and determines an element's properties.

Properties of elements in the same group

They have similar properties.

Semiconductors

Boron and antimony are good examples based on periodic table location.

Unreactivity

This is NOT a property of metals.

Metals

There are more metals than nonmetals.

Metalloid

An element that is a poor conductor under some conditions and good under others.

Nonmetals

Elements on the right side of the periodic table (p-block) mostly have properties of these.

Electron configuration of silicon

[Ne] 3s2 3p2, placing silicon in Period 3.

Group of nitrogen

Group 5A, based on its electron configuration 1s2 2s2 2p3.

Noble gases classification

Neutral atoms with s2p6 configuration in highest energy level.

Groups filling p orbitals

Groups 3A through 8A.

Elements in a period with filled s and p sublevels

There are 8 elements.

Valence electrons location

In the highest energy level.

Group number relation to highest occupied level

Equal to the representative group number (plus 0) for Groups IIIA through VIIIA.

Valence electrons in Group 1 elements

1 valence electron.

Atomic radius increase down a group

Because the number of energy levels increases.

Shielding effect across a period

Remains relatively constant because electrons are added to the same principal energy level.

Atomic radius definition

One-half the distance between two identical nuclei.

Atoms with smallest radii in alkaline-earth group

Have the highest ionization energies.

Atomic radius trend across a period

Generally decreases as atomic number increases.

Largest atomic radius in third period

Sodium.

Sodium

Chlorine

Which element has the smallest atomic radius?

Cation

A positive ion is called a what?

False statement about ions

When a cation forms, more electrons are transferred to it (this is false).

Charge of a cation

Positive charge.

Metals in Groups 1A, 2A, and 3A

Lose electrons when they form ions.

Lithium

Which element has the smallest ionic radius?

Ionization energy

The energy required to remove an electron from a gaseous atom.

Potassium

Which element has the smallest first ionization energy?

Alkali metals in nature

Occur as compounds.

Electronegativities comparison

Compared with elements on the left side of a period, electronegativities on the right side tend to be higher.

Ionization energy trend

Generally increases as you move left to right from potassium through iron.

Electronegativity trend

It generally increases from left to right across a period.

Cesium

Which element has the lowest electronegativity value?

Group 1A

Which group is known as the alkali metals?

Group 2A

Which group is known as the alkaline earths?

Group 7A

Which group is known as the halogens?

Group 8A

Which group is known as the noble gases?

Group 6A

Which group is known as the chalcogens?

Metalloids

Region that bridges metals and nonmetals; they have properties of both metals and nonmetals.

Phosphorus and sulfur

Which two are most similar and why? Both are nonmetals with similar properties.

Xenon and helium

What can be predicted about them? They have similar properties as noble gases.

Metals classification

Approximately what percent of elements are classified as metals? About 80%.

Period 3 orbitals

Which orbitals are filled in an element of period 3 with filled s and p sublevels? 1s, 2s, 2p.

Li+ electron removal

From which orbital is an electron removed when lithium forms Li+? 2s orbital.

Iodine ion formation

What orbital is filled when iodine gains an electron to become an ion? 5p orbital.

Group 7A elements

In which group are the elements with the highest electronegativity values?

Xenon reactivity

Why is xenon generally unreactive? Because it is a noble gas with a full valence shell.

Neutral nickel d sublevel

How many electrons are present in the d sublevel of neutral nickel? 8 electrons.

Group 5A highest occupied energy level

How many electrons are in the highest occupied energy level of Group 5A elements? 5 electrons.

Group 8A highest occupied energy level

How many electrons are in the highest occupied energy level of Group 8A elements? 8 electrons.

Group 4A highest occupied energy level

How many electrons are in the highest occupied energy level of Group 4A? 4 electrons.

Group 3A highest occupied energy level

How many electrons are in the highest occupied energy level of Group 3A? 3 electrons.

Rubidium ion (Rb+)

How many electrons are in a rubidium ion (Rb+)? 36 electrons.

Francium ion (Fr+)

How many electrons are in a francium ion (Fr+)? 86 electrons.

Lithium ion (Li+)

How many electrons are in a lithium ion (Li+)? 2 electrons.

Sodium ion (Na+)

How many electrons are in a sodium ion (Na+)? 10 electrons.

Ca2+ electrons

How many electrons does Ca2+ contain? 18 electrons.

S2- electrons

How many electrons does S2- contain? 18 electrons.

O2- electrons

How many electrons does O2- contain? 10 electrons.

F- electrons

How many electrons does F- contain? 10 electrons.

Group 7A ion charge

What is the usual charge on an ion from Group 7A? -1.

Group 6A ion charge

What is the usual charge on an ion from Group 6A? -2.

Group 1A ion charge

What is the usual charge on an ion from Group 1A? +1.

Group 2A ion charge

What is the usual charge on an ion from Group 2A? +2.