Thermal Energy Question

[physicsstudent111]

Homework Statement

How much energy is required to change one quarter of 8.0 kg of water at 25 degrees celsuis into steam(100 degrees celcuis)

Relevant Equations

Q=mct
Q=mLv

Q=Qwarm water+Qsteam
Q=mct+mLv
Q=(8kg)(4200J)(100C-25C)+(2kg)(2.3*10 to the power of 6 J/Kg)
Q=7.12*10 to the power of 6 J
Is this the correct answer?

 

[malawi_glenn]

Why only 2kg water turning to steam?

 

[physicsstudent111]

Because that's what the question states

 

[malawi_glenn]

Ah great, I missed the one quarter.

Answer is correct. Keep in mind correct significant digits and usage of prefix

 

[physicsstudent111]

Thank you!