chemistry 232- first midterm

midterm 1

condensation

gas→ liquid

deposition

gas→ solid

sublimation

solid→ gas

evaporation

liquid→ gas

normal boiling point

The normal boiling point of a liquid is the temperature at which its vapor pressure equals 1 atm

melting point

The melting point of a solid is the temperature at which it changes from the solid phase to the liquid phase.

fusion curve

A graphical representation of the relationship between temperature and pressure at which a substance transitions from solid to liquid.

What is the relationship between pressure and solid formation in liquids?

This means that as pressure is applied to the liquid, molecules are forced closer together and the solid forms. More closely packed molecules are higher in density.

What does the kinetic energy of a gas depend on?

The kinetic energy of a gas depends only on its temperature, so all of these atoms have the same kinetic energy.

What happens to the temperature during the melting of a solid?

When a solid is converted to a liquid, heat is absorbed.

Temperature remains constant while all of a solid is converted to a liquid

endothermic

process that absorbs heat, resulting in a temperature plateau during phase changes such as melting.

• subliming

• melting

• vaporization

Endothermic Reaction = You're absorbing energy

Now imagine it’s 8 AM, you're dead tired, no glam, no makeup, and you need to absorb energy just to get up and function.

inward( absorbed)

So you make a matcha latte 🍵 or take a hot shower 🚿 — you’re absorbing energy from these things to glow up.

😴➡✨ = Endothermic

➤ You’re pulling in energy
➤ Surroundings feel cooler
➤ Like melting ice — it needs to absorb heat to melt

❄ Ice melting = Endothermic
🧖‍♀ Heating up a face mask = Endothermic
💅 Doing skincare to revive yourself = Endothermic

📝 Keyword: "ENter" = ENdothermic

exothermic

process that releases heat, causing a temperature increase in the surroundings during phase changes such as freezing.

• deposition

• condensation

• freezing

• EXit

• Exothermic Reaction = You're giving off energy

  You're SO excited for the night out, you're literally radiating energy. You're dancing around your room, blasting music, giving off heat like the queen you are.

  💁‍♀💃 = Exothermic

  ➤ Energy is leaving you (released)
  ➤ Surroundings feel warmer
  ➤ Like when a candle burns — it gives off heat to the world

  🕯 Fire = Exothermic
  🥵 Burning calories = Exothermic
  ❤ Giving love (and drama) = Exothermic

  📝 Keyword: "EXit" = EXothermic

• Outward (released

What does the equation T2 = V2 * T1 / V1 represent?

T2=V2*T1/V1

Vapor pressure is inversely related to IMF strength.

• Stronger IMFs = harder to escape into gas phase = lower vapor pressure

• Weaker IMFs = easier to escape into gas phase = higher vapor pressure