Chemistry Practice Test #1

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

The periodic trend for first ionization energy increases as we go __________ in the periodic table.

up and right

What does effective nuclear charge correlate with in terms of ionization energy?

Higher effective nuclear charge increases first ionization energy.

What will happen to the Mg(OH)2 solution upon adding a strong acid?

No effect on Mg2+ ions

Decrease the number of Mg2+ ions in solution

Increase the number of Mg2+ ions in solution (correct)

Cause Mg(OH)2 to precipitate

What happens to the temperature when a strong acid is added to a solution containing OH-?

Temperature increases. Signup and view all the answers

What are the K units for the zeroth law of thermodynamics?

M^1s^-1 Signup and view all the answers

What are the K units for the first law of thermodynamics?

s^-1 Signup and view all the answers

What are the K units for the second law of thermodynamics?

M^-1s^-1 Signup and view all the answers

What are the K units for the third law of thermodynamics?

M^-2s^-1 Signup and view all the answers

Match the following thermodynamic changes with their spontaneity characteristics:

-ΔH = Spontaneous reaction +ΔH = Non-spontaneous reaction -ΔH, -ΔS = Spontaneous at low temperature +ΔH, +ΔS = Spontaneous at high temperature Signup and view all the answers

What is the formula for osmotic pressure?

Π = iMRT Signup and view all the answers

What does R represent in the osmotic pressure formula?

0.082 (L × atm)/(mol × K) Signup and view all the answers

What type of bond is formed between an electronegative nonmetal and a less electronegative nonmetal?

Polar covalent bond Signup and view all the answers

Why does H2O have slightly smaller bond angles than CH4?

Lone pairs repel bonding pairs more strongly Signup and view all the answers

What is the freezing point of pure water?

0°C / 32°F / 273K Signup and view all the answers

Why does pure water have the same melting point and freezing point?

Because they are essentially the reverse of each other. Signup and view all the answers

What is the boiling point of pure water at 1 atm?

100 °C Signup and view all the answers

What does 'Tf' stand for in the freezing point depression formula?

Tf = -(i x Kf x m) Signup and view all the answers

What is the relationship between the number of particles ('i') and freezing point depression?

The more particles, the larger the decrease in freezing point. Signup and view all the answers

Physical changes do not involve changes to the chemical formula of a compound and yield the same product.

True Signup and view all the answers

Which concentrations are necessary to determine the Ksp of NaCl dissolving in H2O?

Concentration of Na+ and Cl- in solution. Signup and view all the answers

What is the relationship between ideal gases X and Y in terms of pressure and volume?

P1V1 = P2V2 Signup and view all the answers

Study Notes

Ionization Energy

First ionization energy increases up and to the right on the periodic table.
It measures the energy required to remove the first electron from a neutral atom.
Effective nuclear charge correlates with first ionization energy; increased attraction from protons makes ionization more difficult.

Chemical Reactions and Equilibria

Adding a strong acid to a saturated solution of Mg(OH)2 causes more Mg2+ ions to form as OH- ions combine with H+ ions to produce water.
The equation representing this reaction is: Mg(OH)2(s) ⇌ Mg2+(aq) + 2OH−(aq).

Thermodynamic Laws and Units

The units for the Zeroth Law are M¹s{¹.
The units for the First Law are s{¹.
The units for the Second Law are M{¹s{¹.
The units for the Third Law are M{²s{¹.

Gibbs Free Energy and Spontaneity

ΔH > 0 and ΔS < 0 indicates a non-spontaneous reaction.
ΔH < 0 and ΔS < 0 indicates spontaneity at low temperatures.
ΔH > 0 and ΔS > 0 indicates spontaneity at high temperatures.
ΔH < 0 and ΔS > 0 indicates spontaneity regardless of temperature.

Osmotic Pressure

The osmotic pressure formula is π = iMRT, where R = 0.082 (L × atm)/(mol × K).

Bonding and Electronegativity

A polar covalent bond occurs when an electronegative nonmetal bonds with a less electronegative nonmetal, e.g., HCl.
Chlorine's high electronegativity results in unequal sharing of electrons, leading to electron density around chlorine.

Entropy and Temperature

Increasing temperature increases the movement of molecules in a system, resulting in greater entropy.
Changes in temperature, volume, and pressure correlate with changes in entropy (ΔS).

Factors Affecting Bond Angles

Lone pairs exert a stronger repulsive force than bonding pairs, which reduces bond angles in molecules.

Redox Reactions

In the reaction 2 Al2O3 + 3 C → 4 Al + 3 CO2, Aluminum in Al2O3 is reduced, while carbon is oxidized.
The description of compounds and changes in oxidation state is crucial for identifying the correct redox processes.

Acid-Base Chemistry

Conjugate pairs relate an acid and its corresponding base:
- Acid loses a proton (H⁺) to form its conjugate base.
- Base gains a proton (H⁺) to form its conjugate acid.

Properties of Water

The freezing point and melting point of pure water are both 0°C / 32°F / 273K.
Pure water can exist in both liquid and solid states at 0°C, depending on heat transfer direction.

Freezing Point Depression

The formula for freezing point depression is ΔTf = -(i × Kf × m), where m is molality, defined as moles of solute per kilogram of solvent.
Adding solute lowers the freezing point of a solution; more particles result in a greater decrease in freezing point.

Changes of State

Physical changes do not alter the chemical formula of a compound and result in the same product, for example, the phase change of aluminum from solid to liquid.

Solubility Product Constant (Ksp)

To determine the Ksp for NaCl dissolving in H2O, consider the concentrations of Na+ and Cl- ions in solution, as solids and pure liquids are excluded from equilibrium expressions.

Ideal Gas Law

For two ideal gases X and Y at the same temperature and molecule number, the relationship of pressure and volume is given by P1V1 = P2V2.
If gas X's pressure is twice that of gas Y, V1 will equal half of V2.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz focuses on the concept of first ionization energy and its periodic trends. Test your knowledge on how ionization energy changes across the periodic table. Understand effective nuclear charge and its relationship to ionization energy.