Chapter 11 - Mastering Chemistry Study Questions

What happens to these physical properties as the strength of intermolecular forces increases? -What decreases? (1)

- vapor pressure

Place these hydrocarbons in order of decreasing boiling point. Rank from highest to lowest boiling point. To rank items as equivalent, overlap them. hexadecane, C16H34 paraffin, C25H52 octane, C8H18 2,2,4-trimethylpentane, C8H18 propane, C2H8

(even using the picture is enough, but looking up boiling points works also) Greatest -> Least 1) paraffin, C25H52 2) hexadecane, C16H34 3) octane, C8H18 4) 2,2,4-trimethylpentane, C8H18 5) propane, C2H8

What happens to these physical properties as the strength of intermolecular forces increases? -What increases? (4)

- melting point - boiling point - viscosity - surface tension

Rank these items in order from greatest mass, to the least mass, from left to right. (greatest -> lease) 1 L of substance in the solid phase 1 L of substance in the liquid phase 1 L of substance in the gas phase

1 L of substance in the solid phase = 1 L of substance in the liquid phase (least mass) 1 L of substance in the gas phase

Based on the general trends on intermolecular forces, rank C2H5OH, HCl, and C3H6 in order of increasing boiling point.

C3H6 < HCl < C2H5OH

Identify the predominant type of intermolecular force in each of the following compounds. Which of theses are London Dispersion Forces? CF4 CHF3 OF2 HF

CF4

Identify the predominant type of intermolecular force in each of the following compounds. Which of theses are Dipole-Dipole Forces? CF4 CHF3 OF2 HF

CHF3 OF2

What is the predominant intermolecular force in the liquid state of each of these compounds: dichloromethane (CH2Cl2)?

Dipole-Dipole

Identify the predominant type of intermolecular force in each of the following compounds. Which of theses are Hydrogen Forces? CF4 CHF3 OF2 HF

HF

Place these hydrocarbons in order of decreasing boiling point. propane octane 2,2,4 trimethylpentane hexadecane paraffin

Highest Boiling Point -> Lowest Boiling Point paraffin, C25H52 hexadecane, C16H34 octane, C8H18 2,2,4-trimethylpentane C8H18

What is the predominant intermolecular force in the liquid state of each of these compounds: water (H2O)?

Hydrogen Bonding

What is the predominant intermolecular force in the liquid state of each of these compounds: carbon tetrafluoride (CF4)?

London - Dispersion Force

Choose the substance with the highest boiling point. CS2 HF Na Cl I 2 CH4

NaCl

Identify the states of matter and the processes that occur at each of the positions on the graph. Solid, Liquid, Gas Melting point, Boiling point

Solid, melting point, liquid, boiling point, gas

When popcorn is heated over a flame, the kernel burst open. Why does this occur? -The skin of the kernel is expanding. -The flesh of the corn is expanding. -The air and water vapor inside the corn kernel is expanding.

The air and water vapor inside the corn kernel is expanding.

Define triple point.

The temperature and pressure where liquid, solid, and gas are equally stable and are in equilibrium.

What is the strongest type of intermolecular force present in NH2CH3?

We do have Dipole-Dipole, Dispersion, and Hydrogen Bonding. But, remember that I H D L order, meaning that Hydrogen Bonding is the strongest

If the pressure of water vapor is increased at a constant temperature of 100 degrees Celsius, it will __________.

condense

If the pressure of water vapor is increased at a constant temperature of -50 degrees Celsius, it will

deposit

The forces between polar molecules is known as ________.

dipole-dipole forces

What is the strongest type of intermolecular force present in F 2?

dispersion forces

Classify which of these are exothermic. freezing condensing deposition subliming melting vaporizing

freezing condensing deposition

A substance with no fixed volume or shape

gas

The liquid that causes the greatest height differential (h) in the manometer has the _____ vapor pressure and therefore the _____ intermolecular forces.

greatest vapor pressure weakest intermolecular forces

Atmospheric pressure decreases as altitude increases. In other words, there is more air pushing down on you at sea level, and there is less air pressure pushing down on you when you are on a mountain. If hexane (C6H14), heptane (C7H16), and heptanol (C7H15OH) are heated evenly at different altitudes, rank them according to the order in which you would expect them to begin boiling. Rank from first to last. To rank items as equivalent, overlap them.

hexane at high altitude heptane at high altitude heptane at sea level heptanol at sea level

The two strands in DNA are held together by ________ bonds.

hydrogen

Rank the following types of intermolecular forces in general order of decreasing strength (strongest to weakest). Ion-dipole Dipole-dipole Hydrogen bonding London dispersion

ion-dipole hydrogen bonding dipole-dipole London dispersion I.H.D.L.

A substance with a fixed volume and no fixed shape is a _________.

liquid

If ice is heated at a constant pressure of 1 atm, it will ______.

melt

A substance with a fixed volume and fixed shape is a __________.

solid

If ice is heated at a constant pressure of 0.00512 atm, it will _________.

sublime

Classify which of these are endothermic. freezing condensing deposition subliming melting vaporizing

subliming melting vaporizing