Answer:
ummmm... whats this supposed to mean? any answer choices
Explanation:
17. ΔH rxn is the enthalpy of a reaction. It is the amount of energy or heat absorbed in a reaction. If enthalpy is positive, it means the reaction absorbs heat, which means it is endothermic. If the enthalpy is negative, it means the reaction release heat, which means it is exothermic.
18. yes, it is possible in theory but it is not necessary. Water is the ideal, cheaper, and most abundant liquid for a calorimeter.
19. Specific heat= heat/mass*Temp. the mass is already known You can place the piece of metal in a calorimeter filled with water. the piece of metal and water must be at different temperatures. Ideally, you would heat up the water and let it cool down. This change in temperature in the temperature that goes into the formula for the piece of metal. The only missing value is the heat which can be easily calculated because water' specific heat is known which can be used to calculate the heat loss by the water, which is the same as the heat gain by the piece of metal. With all the three values calculated and measured, you can simply plug them into the formula and solve for the specific heat of the metal.
Explanation of the strategy: 1) calculate the mass of water and convert to number of moles, 2) convert the mass of anhydrous CuSO4 to moles, and, 3)calculate the mole ratio of water to CuSO4 anhydrous
1) Calculate the mass of water:
mass of water = mass of the hydrate CuSO4 - mass of the anhydrous compound
mass of water = 12.98 g - 9.70 g = 3.28g
2) Calculate the number of moles of water
number of moles = mass in grams / molar mass
molar mass of water = 18.01 g/mol
number of moles of water = 3.28 g / 18.01 g/mol = 0.182 mol
3) Calculate the number of moles of CuSO4 anhydrous
number of moles = mass in grams / molar mass
molar mass of Cu SO4 = 159.6 g/mol
number of moles of CuSO4 = 9.70g / 159.6 g/mol = 0.0608 moles
4) Calculate the ratio moles of water / moles of CuSO4
ratio = moles of water / moles of CuSO4 = 0.182 / 0.0608 = 2.99 ≈ 3
Therefore the molecular formula is CuSO4 . 3H2O
Name: copper(II) sulfate trihydrate.
Answer:
All ions must a overall charge
Explanation:
