HNO3+KOH = H2O+KNO3 . When nitric acid react with pottasuim hydroxide, the reaction will produce water (H20) and pottasuim trioxonitrate
Answer:
a. -29.8 kJ/mol-rxn
Explanation:
For a chemical reaction system the forward and reverse rate are equal. The standard molar enthalpy formation of NH3 is -45.9 kJ/mol. For the enthalpy of NH3 (8) the molar enthalpy is -29.8kJ/mol. The molar mass of N2 = 28.02g/mol. Molar enthalpy of formation is standard amount of substance produced in the formation of a reaction. The molar enthalpy is the change in enthalpy due to reaction per mole.
Given:
128g sample of titanium
2808J of heat energy
specific heat of titanium is 0.523 J/ g °C.
Required:
Change in temperature
Solution:
This can be solved
through the equation H = mCpT
where H is the heat, m is the mass, Cp is the specific heat and T is the change in temperature.
Plugging in the
values into the equation
H = mCpT
2808J = (128g) (0.523
J /g °C) T
T
= 41.9 °C
Answer:
A) Melting
Explanation:
The three changes of phase described in this problem are:
- Melting: melting occurs when a substance in solid state turns into liquid state. Since molecules in liquid state have more energy than molecules in solid state (because in liquids, molecules can slide past each other, while in solids they can't move, but only vibrate), thermal energy must be added in order to melt a substance
- Freezing: freezing occurs when a liquid substance turns into solid state (the opposite of melting). Since molecules in liquid state have more energy than molecules in solid state, thermal energy must be removed from the substance in order to cause freezing
- Condensation: condensation occurs when a gaseous substance turns into liquid state. Since molecules in gaseous state have more energy than molecules in liquid state, thermal energy must be removed from the substance in order to cause condensation
So the correct option is
A) melting