Chemistry: Gases, Liquids, and Solids Key Concepts for Students for quiz

What describes a gas that will not condense because the molecules do not attract each other?

An ideal gas.

What is the formula for kinetic energy?

KE = ½ mv².

What happens to the kinetic energy of colliding particles during an elastic collision at constant temperature?

The energy is transferred between them.

If two gases have the same temperature and energy but different molecular masses, which molecules will have greater speed?

The molecules with the lower molecular mass(the smaller one.)

Why does a strong-smelling gas released in a room quickly spread throughout the area?

Gas molecules are in constant, rapid, random motion.

What happens to the rate of effusion of a gas as it is heated?

The rate of effusion increases as the speed of the molecules increases.

What is the relationship between average kinetic energy and temperature for gases?

The average speed of the molecules is proportional to temperature.

What causes polar gas molecules to deviate more from ideal behavior than nonpolar molecules?

Polar molecules attract neighboring polar molecules, affecting their straight-line paths.

In terms of effusion, how are gases ranked based on their molar mass?

Gases are ranked from heaviest to lightest, as heavier molecules have slower average speeds.

What distinguishes intermolecular forces from intramolecular forces?

Intermolecular forces are between separate molecules, while intramolecular forces are within individual molecules.

What effect does the mobility of liquid molecules have on their shape?

Liquid molecules are mobile, allowing them to take the shape of their container without expanding to fill it.

Why do polar liquids evaporate more slowly than nonpolar liquids?

Polar molecules are attracted to each other, making it harder for them to escape from the liquid's surface.

What is a characteristic of ionic crystals?

Ionic crystals are hard, brittle, and nonconducting.

What type of solid is characterized by strong covalent bonds between neighboring atoms?

Covalent network crystals.

What happens when a chunk of solid lead is dropped into molten lead?

The solid lead sinks, indicating it is denser than the molten lead.

Which type of solid is sometimes described as a supercooled liquid?

Amorphous solid.

What is the normal boiling point of CCl4 based on vapor pressure data?

The normal boiling point of CCl4 is about 76°C.

What must the air pressure be for water to boil at a reduced pressure of 60 kPa?

The boiling point of water will be lower than its normal boiling point at 101.3 kPa.

What makes water vapor less volatile than CCl4?

Water's strong hydrogen bonding makes it less volatile compared to CCl4.

What makes water less volatile than CCl4 despite its smaller molar mass?

Water is polar and has strong hydrogen bonds, while CCl4 is nonpolar with weak intermolecular forces.

What is the density relationship between ice and liquid water?

The density of ice is less than the density of liquid water.

What is the molecular composition of a water molecule?

A water molecule contains one atom of oxygen and two atoms of hydrogen.

What type of bonding occurs between water molecules?

Hydrogen bonding occurs between a hydrogen atom of one water molecule and the unshared pair of electrons of an oxygen atom of an adjacent water molecule.

What effect does hydrogen bonding have on the boiling point of water?

Hydrogen bonding causes the boiling point of water to be relatively high.

Which liquid has a higher boiling point: water or formaldehyde (CH₂O)?

Water has a higher boiling point than formaldehyde.

Which liquid is more volatile: water or formaldehyde?

Formaldehyde is more volatile than water.

Which liquid has a higher surface tension: water or formaldehyde?

Water has a higher surface tension than formaldehyde.

In which liquid is NaCl more likely to be soluble: water or formaldehyde?

NaCl is more likely to be soluble in water.

What happens to the volume of a gas when it is condensed to a liquid?

The volume shrinks by a factor of about 1000.

What happens to the pressure of a gas in a rigid container when it is warmed?

The pressure increases as the temperature increases.

Which state of matter is less compressible: solids or liquids?

Solids are less compressible than liquids.

Which state of matter has a definite volume and shape?

Solids have a definite volume and shape.

Which state of matter diffuses more quickly: liquids or gases?

Gases diffuse more quickly than liquids.

What is the critical temperature of a substance?

The critical temperature is the temperature above which a substance can only exist as a gas.

Which noble gas is stable as a liquid at 0°C?

Xenon (Xe) is stable as a liquid at 0°C.

What is the relationship between molar mass and boiling points among nonpolar liquids?

Among nonpolar liquids, those with higher molar masses tend to have higher boiling points.

What is the relationship between polarity and enthalpy of vaporization among compounds of similar molar mass?

Compounds with greater polarities tend to have higher enthalpies of vaporization.

What is a physical change?

A change in a substance that does not involve a change in the identity of the substance

What is a chemical change?

A change in matter that produces one or more new substances

What is freezing?

liquid to solid

What is melting?

solid to liquid

What is condensation?

gas to liquid

What is evaporation?

Liquid to gas

What is sublimation?

What is deposition?

gas to solid