Calculate the heat necessary to raise the temperature of 40.0 g of aluminum from 20.0 C to 700.0 C

We need 40.4 kJ to raise the temperature to 700.0 °C

Explanation:

Step 1: Data given

Mass of aluminium = 40.0 grams

Specific heat of aluminium = 0.900 J/g°C

The initial temperature = 20.0 °C

The final temperature = 700.0 °C

The melting point of aluminium = 660.3 °C

Step 2: Calculate heat needed to raise aluminium from 20.0 °C to 660.3 °C

Q = m*C*ΔT

⇒with Q = the heat needed = TO BE DETERMINED

⇒with m =the mass of aluminium = 40.0 grams

⇒with c = the specific heat of aluminium = 0.90 J/g°C

⇒with ΔT = the change of temperature = T2 - T1 = 660.3 - 20.0 = 640.3 °C

Q = 40.0 * 0.900 * 640.3

Q = 23050.8 J

Step 3: Calculate heat need to melt aluminium

Q = m*ΔHfusion

Q = 40.0 g*398 J/g

Q = 15920 J

Step 4: Calculate heat needed to raise aluminium from 660.3 to 700.0°C

Q = m*C*ΔT

⇒with Q = the heat needed = TO BE DETERMINED

⇒with m =the mass of aluminium = 40.0 grams

⇒with c = the specific heat of aluminium = 0.90 J/g°C

⇒with ΔT = the change of temperature = T2 - T1 = 700 - 660.3 = 39.7 °C

Q = 40.0 * 0.90 * 39.7

Q = 1429.2 J

Step 5: Calculate the total heat needed

Q = 23050.8 + 15920 + 1429.2

Q = 40400 J = 40.4 kJ

We need 40.4 kJ to raise the temperature to 700.0 °C

the volume increases

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.