CHEMISTRY 2: Stoichiometry, Chemical Bonds

Question 1

Is the study of quantitative aspects of chemical formulas and chemical reaction

Answer 1

Stoichiometry

Question 2

Amount of any substance that contains the same number of elementary entities as there are atoms in 12g of 12c

Answer 2

Mole

Question 3

Is the mass per mole of entities (atoms, molecules or formula units)

Answer 3

Molar Mass

Question 4

Familiarize stoich map

Answer 4

GO NAAA

Mass → Mole = Mass/Molar Mass
Particles→ mole = Atoms/Avogadro’s number

Mol → Mass = Mol x Molar Mass
Mol → Particle = Mol x Avogadro’s number

palabas ang times, paloob divide (arrow)

Question 5

→ Is the quantitative relationship between the amounts of reactants used and amounts of products formed in a reation

→Expressed in balanced equationExpressed in balanced equation

Answer 5

Chemical Stoichiometry

Question 6

Formula of Percent Yield?

Answer 6

% yield = Actual yield/Theoretical yield (100)

Question 7

→ The amount of product that could possibly be produced in a given reaction

→ Calculated according to the starting amount

Answer 7

Theoretical yield

Question 8

→ The amount of product actually obtaiend in a chemical reaction

Answer 8

Actual yield

Question 9

→ A chemical reactant that limits the amount of product that is formed

Answer 9

Limiting reactant

Question 10

→ Gives smallest yield of product calculated from the reagents available

Answer 10

Limiting agent

Question 11

→ Is the reactant in a chemical reaction with a greater amount than necessary to react completely with the limiting reactant

Answer 11

Excess reactant

Question 12

Formula and Composition

Shows the simplest ratio of elements in a molecular compound

Answer 12

Empirical formula

Question 13

Shows the number and type of atoms that make up a molecule

Answer 13

Molecular formula

Question 14

Atoms combine, electron distribution changes

Answer 14

Chemical Bonds

Question 15

What are the 3 types of chemical bonds?

Answer 15

1. Covalent bond
2. Ionic bond
3. Metallic bond

Question 16

3 types of chemical bonds

Results from shairng of electrons between atoms. Found between nonmetals

Answer 16

Covalent bonding

Question 18

3 types of chemical bonds

Results from transfer of electrons from a metal to a non metal

Answer 18

Ionic bonding

Question 19

3 types of chemical bonds

Outer electrons move throughout solid and holds nuclei together and the compound is only composed of metals

Answer 19

Metallic bond

Question 20

Allows us to draw shape of a molecule which helps us to understand its properties

Answer 20

Lewis Structure

Question 21

→ Some atom atomd in the third row of the periodic table and beyond can acommodate 4 paiard of electrons

→ Termed a central atom and the atoms bonded to it are called outer atoms

Answer 21

Hypervalent Atoms

Question 22

→ A tool used to represent certain types of molecular structures

→ Arises when no single conventional model using only single double or triple bond can account for all the observed properties of the molecule

Answer 22

Resonance

Question 23

→ Used to evaluate non-equivalent Lewis structures

→ no. of valence electron in free state -no. of nonbonding electrons - no. of bonds

Answer 23

Formal charge

Question 24

Is a set of empirical rules for predicting a molecular geometry using, as input, a correct lewis dot representation

Answer 24

Valence Shell Electron Pair Repulsion (VSEPR)

Question 25

Distribution of regions of high electron density around the central atom

Answer 25

Electronic geometry

Question 26

Arrangement of atoms around the central atom

Answer 26

Molecular geometry

Question 27

T or F

If lone pairs are present, molecular and electronic geometries are samae

Answer 27

F (they are different, same if no lone pairs are present)

Question 28

Dipole momements for all bonds cancel out

Answer 28

Nonpolar molecule

Question 29

Dipole moments for all bonds don’t cancel out/ has net dipole moment

Answer 29

Polar molecule

Question 30

→ Is the force that holds molecules together

→A form of “stickiness” between molecules

Answer 30

Intermolecular Force of Attraction (IMFA)

Question 31

What are the 4 types of Intermolecular Forces of Attraction

Answer 31

1. London Dispersion Forces
2. Dipole-dipole forces
3. Hydrogen bonding
4. Ion-Dipole Forces

Question 32

4 Types of Intermolecular Forces of Attraction

→ Called “Induced dipole forces or dispersion forces”

→ Temporary dipole attraction between non polar molecules that form due to shifting electrons

→ Electrons concentrate in one region, which results in temporary dipole that disappears when the electrons shift again

→ Temporary partially negative charge and partially positive charge forms

Answer 32

London Dispersion Forces

only type of IMF between nonpolar molecules (weakest since temporary)

Question 33

Familiarize the the process of London Dispersion Forces

Answer 33

1.Temporary dipole appears when electrons shift within one of the nucleus

2.Adjacent molecule will be attracted to the molecule with temporary dipole and a new dipole within the second molecule will be induced

3.Electrons move back and temporary dipole disappears

Question 34

4 Types of Intermolecular Forces of Attraction

→ A permanent dipole force exists between polar molecules

→Attraction form between the partially positive and partially negative ends of adjacent polar molecules

Answer 34

Dipole-dipole forces

Stronger than london dispersion forces since these are permanent

only polar molecules can form dipole-dipole

Question 35

4 Types of Intermolecular Forces of Attraction

→ Strong dipole force exists between molecules containing** H-F, H-O or H-N** bonds (high polar due to large electronegativity difference)

Answer 35

Hydrogen bonding

very strong type of IMF between polar molecules

Question 36

4 Types of Intermolecular Forces of Attraction

→ When an ionic compound such as NaCl dissolves in water, the water molecules arrange their oppositely charged dipole to be attracted to fully charged ion creating a very strong attractive force

Answer 36

Ion-Dipole Forces