A container holds 8.0kg of water at 25degC....

[MaryBarnes]

Homework Statement

how much energy must be added to the water to create 2.0 kg of steam?

Homework Equations

The Attempt at a Solution

I have no idea how I am supposed to figure the answer out. what formulas do I use?

 

[americanforest]

What formula do you know that is related to heating and/or transforming material from one physical state to another? Those are the two processes which must occur here.

 

[MaryBarnes]

What formula do you know that is related to heating and/or transforming material from one physical state to another? Those are the two processes which must occur here.

q=mL_v

 

[MaryBarnes]

i attempted the answer:

Q total=mc_wΔt+m_sL_f
=8.0kg*4200j/kg*(100°C-25°C)+2.0kg*2.3*10⁶
=7.12*10⁶J

 

[haruspex]

i attempted the answer:

Q total=mc_wΔt+m_sL_f
=8.0kg*4200j/kg*(100°C-25°C)+2.0kg*2.3*10⁶
=7.12*10⁶J

Yes.
If you want to make your working letter-perfect, include all units: 8.0kg*4200J/kg/°C*(100°C-25°C)+2.0kg*2.3*10⁶J/kg.

 

[MaryBarnes]

Yes.
If you want to make your working letter-perfect, include all units: 8.0kg*4200J/kg/°C*(100°C-25°C)+2.0kg*2.3*10⁶J/kg.

awesome! thanks for the help!