Respuesta :
Answer:
67.5°C will be the final temperature of the water.
Explanation:
Density of water = 1 g/ml
mass = Density × Volume
Mass of 20 mL water = [tex]m_1[/tex]
[tex]m_1=1 g/ml\times 20 mL=20 g[/tex]
Mass of 60 mL water = [tex]m_2[/tex]
[tex]m_2=1 g/ml\times 60 mL=60 g[/tex]
Heat gained by water at 30°C will be equal to heat lost by the water at 80°C
[tex]Q_1=-Q_2[/tex]
Mass of water at 30°C= [tex]m_1=20 g[/tex]
Specific heat capacity of water = [tex]c_1=4.184 J/g^oC [/tex]
Initial temperature water at 30°C = [tex]T_1=30^oC[/tex]
Final temperature after mixing = [tex]T_2[/tex]=T
[tex]Q_1=m_1c_1\times (T-T_1)[/tex]
Mass of water at 80°C= [tex]m_2=60 g[/tex]
Specific heat capacity of water at 80°C= [tex]c_2=4.184 J/g^oC [/tex]
Initial temperature of the water at 80°C= [tex]T_3=80^oC[/tex]
Final temperature of water after mixing= [tex]T_2[/tex]=T
[tex]Q_2=m_2c_2\times (T-T_3)[/tex]
[tex]Q_1=-Q_2[/tex]
[tex](m_1c_1\times (T-T_1))=-m_2c_2\times (T-T_3)[/tex]
[tex](m_1\times (T-T_1))=-m_2\times (T-T_3)[/tex]
On substituting all values:
[tex](20 g\times (T-30^oC))=-[60 g\times (T-80^oC)][/tex]
we get, T = 67.5 °C
67.5°C will be the final temperature of the water.
