A container has #12 L# of water in it at #90 ^o C#. An object with a specific heat of #750 (KJ)/(Kg*K)# and a temperature of #250 ^oC# is placed into the container. If the water is completely vaporized, what is the object's mass?

1 Answer
Dec 30, 2017

The mass is #0.245" kg"#.

Explanation:

The heat is transferred from the hot object to the cold water.

The temperature of the water is #T_w=90^@"C"#

The temperature of the object is #T_o=250^@"C"#

# m_o C_o (DeltaT_o-100) = m_w C_w (100-90)+m_wH_w#

The specific heat of water is #C_w=4.186kJkg^-1K^-1#

The specific heat of the object is #C_o=750"kJ""kg"^-1K^-1#

The heat of vaporisation of water is #H_w=2257"kJ""kg"^-1#

The mass of the object is #m_0=?kg#

The mass of the water is #m_w=12kg#

# m_o 750 (250-100) = 12 *4.186 (100-90)+12*2257#

#112500m_o=27586#

#m_o=27586/1112500=0.245" kg"#

I hope that helps!