ChemistryUnit 5

Study GuideYou may use this study guide to review for your test; practice your new skills or

review old concepts.Each topic has several questions relating to it,

this should help with giving you plenty of practice.

Ions and Charges

A B C

Valence Structure

A B C

FormulasA B C

Ionization Energy

ABC

Molecular ShapesA B C

Polar/Nonpolar

A B C

Ionic BondsA B C

Covalent BondsA B C

StoichiometryA B C

Balancing EquationsA B C

Electronegativity

A B C

Formulas with

Polyatomic Ions

A B C

Ions and Charges Question A

All elements are trying to achieve what electron

configuration?A noble gas configuration

Ions and Charges Question B

The element Sodium is likely to form an ion of what

charge and why?+1 because it will give away it’s 1 valence electron to achieve a structure like Ne.

Ions and Charges Question C

What charge will the element O be likely to form and why?

-2 because it will want to take 2 electrons to form a full outside shell like the element Ne.

Valence Structure AGiven the electron configuration

1s22s22p3; what element is this and what ion charge will it likely have?

Element Nitrogen, -3 charge on the ion

Valence Structure BAn element has an electron configuration

of 1s22s22p5, what electron configuration will it try to form and

why?1s22s22p6; in order that it have a full outside electron shell like a noble gas.

Valence Structure CHow many valence electrons does the

following element have?1s22s22p63s23p2

4

Formulas AWhat would be the formula for Calcium

bonding with Iodine?

CaI2

Formulas BWhat would be the formula for Cesium

bonding with Phosphorus?

Cs3P

Formulas CWhat would be the formula for Carbon

bonding with Hydrogen?

CH4

Ionization Energy AWhat does ionization energy tell us?

What is an example of an element with low Ionization energy?

Ionization energy tells us how easily and element will give away a valence electron. Any group 1 or 2 element has low ionization energy.

Ionization Energy BWhich elements have very high

ionization energies?

Group 6A (16) and Group 7A (17) elements.

Ionization Energy CWhat is the relationship between

ionization energy and electronegativity?

They act like opposites, an element with low ionization energy will have high electronegativity and vice versa.

Molecular Shapes AWhat shape will a molecule of NH3 form?

pyramidal

Molecular Shapes BWhat molecular shape will the molecule

AlF3 form?

Trigonal planer

Molecular Shapes CWhat shape will water form and why?

Bent, because there are two sets of lone pairs that push the bonds down closer together.

Polar/Nonpolar AIs water a polar or non polar molecule

and why?

It is polar because the oxygen has a slightly negative charge and the hydrogen a slightly positive due to electronegativities and it’s shape.

Polar/Nonpolar BIs CH4 polar or non polar and why?

Nonpolar, because with it’s tetrahedral shape the slightly positive H surround the C and there is no negative and positive end.

Polar/Nonpolar CIs the molecule NH3 polar or nonpolar and what is the difference between it

and AlF3?Ammonia is polar and is different from AlF3 because AlF3 is trigonal planer and the slightly negative charges surround the positive and so there is no + or – end.

Ionic Bonds AHow is an ionic bond formed?

An atom forfeits it’s electrons due to low electronegativity to an atom that has high electronegativity and since the two ions have opposite charges they are drawn together to neutralize the charge.

Ionic Bonds BIf there is an ion with a charge of -2;

name two ways that it’s charge could be neutralized in a bond.

It could bond with an ion with a +2 charge or 2 ions with a +1 charge.

Ionic Bonds CWhat do we call a negative ion? A

positive ion?

Anion; cation

Covalent Bonds AHow is a covalent bond different from an

ionic?

An ionic bond consists of exchange of electrons forming ions, in a covalent bond the electrons are shared between the atom’s electron shells.

Covalent Bonds BWhat types of elements make up a

covalent bond?

2 non metals joined together or in other words elements from groups 4A,5A and 6A.

Covalent Bonds CWhich is stronger an ionic bond or a

covalent bond?

Ionic bond because of the electromagnetic force holding the atoms tightly.

Stoichiometry AIf you are given 17 grams of C how many

grams of water would you need to react with that?

C + H2O → CO + H2

25.5 g of water

Stoichiometry BIf you had 8 L of H2, how many L of O2

would you need to react?2H2 + O2 →2H2O

4L of O2

Stoichiometry CIf you have 12.04 x 1023 molecules of H2O

you have how many grams is that?

32 grams water

Balancing Equations ABalance the equation below:

C3H8 + O2 →CO2 + H2O

1:5:3:4

Balancing Equations BWhy do we balance equations?

So that the law of conservation of mass is satisfied and we can obtain the molar ratio of reactants and products.

Balancing Equations CBalance the equation below:

HCl + Mg(NO3)2 → HNO3 + MgCl2

2:1:2:1

Electronegativity AWhat is electronegativity and what causes it to increase or decrease?

The ability of an atom to pull electrons from another atom and add them to its outside shell. The size of the atom affects it as well as the number of valence electrons. The smaller the atom the higher the electronegativity and the more valence the higher it is.

Electronegativity BOn the metals side of the Periodic Table

what happens to the electronegativity values as you go down a group?

They decrease

Electronegativity CWhat is the most electronegative

element on the Periodic Table?

Fluorine F

Formulas with Polyatomic Ions AWhat is the formula for Cu which has a

+1 charge with nitrate?

CuNO3

Formulas with Polyatomic Ions B

What is the formula for Magnesium acetate?

Mg(C2H3O2)2

Formulas with Polyatomic Ions C

What is the formula for calcium combing with a sulfate ion?

CaSO4