Heat and Thermodynamics

When and with what equation is Heat of Fusion used?

• Q = mHf ; going between solids and liquids

• Q = mHf ; going between liquids and gases

• Q = mHv ; going between solids and liquids

• Q = mHv ; going between liquids and gases

When and with what equation is Heat of Vaporization used?

• Q = mHf ; going between solids and liquids

• Q = mHf ; going between liquid and gases

• Q = mHv ; going between solid and liquids

• Q = mHv ; going between liquid and gases

In both Q=mC∆T and Q=mH , what does the m stand for

• mass

• heat

• change in temperature

• heat of fusion

• heat of vaporization

In both Q=mC∆T and Q=mH , what does the Q stand for

• mass

• heat

• change in temperature

• heat of fusion

• heat of vaporization

In both Q=mC∆T ; what does the ∆T (delta T) represent and how do you find it?

• Change in Temperature = initial T - final T

• Change in Temperature = final T - initial T

• Initial Temperature

• Final Temperature

When and with what equation is delta T (∆T or change in temperature) used?

• Any SLOPED line in the phase change diagram ; Q=mC∆T

• The FLAT line between solid and liquid; Q = mHf

• The FLAT line between liquid and solid Q = mHv

Tags

NGSS.HS-PS1-5

NGSS.HS-PS3-4

If the questions asks about water freezing or melting, you should use...

• Hf = 334 J/g

• Hv = 2260 J/g

Tags

NGSS.MS-PS1-4

What will NOT be present in the question if you need to use heat of fusion or heat of vaporization

• A value for Q (heat)

• A value for m (mass)

• A change in temperature (∆T)

• The word boil

• The word melt

Choose the correct formula for the problem: If 2083 Joules are used to MELT 5.26 grams of aluminum, what is the heat of fusion of aluminum

• 2083 J = (5.26 g) * Hv

• 2083 J = (5.26 g) * Hf

• Q = (5.26 g) * (2083 J/g)

• 2083 J = (5.26 g) * -Hf

Tags

NGSS.HS-PS3-1

Choose the correct formula for the problem: If 5.26 grams of zinc is melted, and it takes 579 Joules to completely melt the sample. What is the

heat of fusion of zinc?

• 579 J = (5.26 g) * Hv

• 579 J = (5.26 g) * Hf

• Q = (5.26 g) * (579 J/g)

• cannot be determined