Trends in Periodic Table
Balancing Equation
Mole Concept
Kinetic Molecular Theory /
Intermolecular Forces
Properties of Liquids
10

What is being described?

Across a period: Generally increases due to increasing nuclear charge.

Down a group: Generally decreases due to increasing atomic size.

Ionization energy / Electronegativity

10

These are the substances that are formed as a result of a chemical reaction. They are present at the end of the reaction and are produced from the reactants.

Products

10

How many particles are present in one mole of a substance?

6.022 x 1023 particles

10

What type of intermolecular force occurs between these polar molecules?

Hydrogen Chloride (HCl)

Dipole - Dipole Interaction

10

Analogy

adhesion < cohesion : _______ meniscus

adhesion > cohesion : _______ meniscus

Answer:

convex meniscus : concave meniscus

20

What is being described?


Across a period: Generally decreases due to increasing nuclear charge pulling the electrons closer.

Down a group: Generally increases due to the addition of energy levels.

Atomic Radius

20

What do you call the numbers written in front of chemical formulas in a balanced chemical equation? 

HINT : They represent the relative amounts of reactants and products involved in the reaction.  

Coefficients

20

What is the difference between a formula unit and a molecule in terms of the mole concept?

Formula unit refers to the simplest ratio of ions in an ionic compound

Molecule refers to a group of atoms bonded together covalently

20

Which type of intermolecular force is primarily responsible for the attraction between sodium ions (Na+) and chloride ions (Cl-) in solid sodium chloride (NaCl)?

Answer:

Ion-Ion Forces of Attraction

20

Which of the following substances would be the most soluble in water? 

a. CH3CH2NH2               b. CH3CH2CH2CH2NH2

c.  CH3CH2CH2Br           d. CH3CH2CH2CH3


Answer:

a. CH3CH2NH2 


30

Which group on the periodic table contains elements with the highest electronegativity?

 Group 17 - The halogens

30

This law states that the total mass of substances does not change during a chemical reaction.

Law of Conservation of Mass

30

Problem: 

Calculate the mass of 3 moles of carbon dioxide (CO2).

Answer:

132.03 grams of CO2

30

Which of the following substances has the highest strength of hydrogen bonding?

a. Water (H2O)

b. Ammonia (NH3

c. Hydrogen fluoride (HF) 

d. Hydrogen sulfide (H2S)  

Answer:

c. Hydrogen Fluoride (HF)


This large electronegativity difference results in a strong dipole moment, with the hydrogen atom carrying a partial positive charge and the fluorine atom carrying a partial negative charge.  

30

Vaporization occurs more readily with ______.


(Give at least two factors)

Answer:

1. Increased temperature

2. increased surface area of the liquid

3. decreased intermolecular forces of attraction

40

Which of the following elements is the most electronegative?

A. Titanium                     B. Gallium                      

C. Phosphorus                 D. Barium  

C. Phosphorus

40

Balance this chemical equation:

Na  +  Cl2   =   NaCl

Balanced chemical equation:

2Na  +  Cl2   =   2NaCl

40

Problem: 

Convert 5.0 x 1024 atoms of oxygen (O) to moles.

Answer:

8.30 moles of Oxygen

40

Which of the following substances exhibits London dispersion forces as its primary intermolecular force? 

a. Methane (CH4)                      b. Water (H2O) 

c. Hydrogen chloride (HCl)         d. Neon (Ne)

Answer:

a. Methane (CH4

Methane (CH4) exhibits London dispersion forces as its primary intermolecular force because it is a nonpolar molecule.

40

For liquids, viscosity decreases with increasing temperature.

For gases, the viscosity increases with increasing temperature.

Describe their relationship.

Answer:

Liquids : inverse relationship.

Solids :  direct relationship.

50

Why does the electronegativity increase across a period?

Increase in effective nuclear charge

Decrease in atomic radius

50

Balance this chemical equation:

C3H8 + O2 = CO+ H2O

C3H8 + 5O2 = 3CO+ 4H2O

50

Problem: 

A scientist has 10 grams of water (H2O). How many molecules of oxygen (O) does the scientist have?

Answer:

≈ 3.34 x 1023 molecules of Oxygen

50

How does temperature relate to the kinetic energy of gas particles according to the kinetic molecular theory?

Temperature is directly proportional to the average kinetic energy of gas particles. 

As temperature increases, the average kinetic energy of gas particles also increases.

50

Liquids with stronger intermolecular forces have more tendency to escape into gas.

True or False? Explain.

FALSE.

Liquids with stronger intermolecular forces have higher cohesive forces, which means they are more tightly held together in the liquid phase. As a result, these molecules have a lower tendency to escape into the gas phase compared to molecules with weaker intermolecular forces.