Answer:
26.2g = Mass of water in the calorimeter
Explanation:
The heat absorbed for the water is equal to the heat released for the metal. Based on the equation:
Q = m*C*ΔT
<em>Where Q is heat, m is the mass of the sample, C is specific heat of the material and ΔT is change in temperature</em>
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Replacing we can write:
13.9g * 0.449J/g°C * (54.2°C-15.6°C) = m(H₂O) * 4.184J/g°C * (15.6°C-13.4°C)
240.9J = m(H₂O) * 9.2J/g
<h3>26.2g = Mass of water in the calorimeter</h3>
Answer:
Mole fraction for solute = 0.1, or 10%
Molality = 6.24 mol/kg
Explanation:
22.3% by mass → In 100 g of solution, we have 22.3 g of HCOOH
Mass of solution = 100 g
Mass of solute = 22.3 g
Mass of solvent = 100 g - 22.3g = 77.7 g
Let's convert the mass to moles
22.3 g . 1mol/ 46 g = 0.485 moles
77.7 g. 1mol / 18 g = 4.32 moles
Total moles = 4.32 moles + 0.485 moles = 4.805 moles
Xm for solute = 0.485 / 4.805 = 0.100 → 10%
Molality → mol/ kg → we convert the mass of solvent to kg
77.7 g. 1 kg / 1000g = 0.0777 kg
0.485 mol / 0.0777 kg = 6.24 m
Answer:
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