Answer:
20.468 kilo Joules is the enthalpy change when one mole of sodium nitrate dissolves.
Explanation:
Heat lost by solution ad calorimeter = Q
Heat capacity of solution ad calorimeter = C = 1071 J/°C
Change in temperature = ΔT = 21.56°C - 25.00°C = -3.44°C


Heat gained by sodium nitrate = -Q = -(-3,684.24 J)=3,684.24 J
Moles of sodium nitrate = 
When 0.18 mole of sodium nitrate was dissolved in water 3,684.24 joulesof heat was absorbed by it.
Then heat absorbed by 1 mole of sodium nitrate :

1 J = 0.001 kJ
20.468 kilo Joules is the enthalpy change when one mole of sodium nitrate dissolves.
Answer:
AgNO2
Explanation:
The question asks to know which of these two insoluble salts is expected to be more soluble in acidic solution than in pure water.
To answer this question specifically, we need to know if the anions contained in the insoluble salt is a conjugate of a weak acid or that of a weak base.
Generally, the solubility of insoluble salts that contain anions which are conjugates of weak acids increases in the presence of an acidic solution than in water. While, the solubility of insoluble salts that contain anions which are conjugates of strong acids decreases in the presence of an acidic solution.
Having said this, AgNO2 contains NO2 which is the conjugate base of the Trioxonitrate iii acid which is a weak acid. Hence, it is expected to be stronger in acidic solution than in water.
Explanation:
the experiment conducted is the student adds sugar to a cup of iced tea and a cup of hot tea. She notices that the time needed for the sugar to dissolve in each cup is different. She thinks this has something to do with the temperature of the tea
hypothesis: If the student puts the sugar in both glasses of tea, then the sugar in the hot tea should dissolve quicker.
Answer: The percent yield of the reaction is 77.0 %
Explanation:




According to stoichiometry:
2 moles of
produces = 2 moles of 
2.18 moles of
is produced by=
of 
Mass of
=
percent yield =
<u>Answer :</u>
Chemical energy - D) Potential energy stored in the bonds between atoms
Electrical energy - C) The movement of an electrical charge
Radiant energy - B) Electromagnetic energy that travels in waves
Thermal energy - A) Internal energy caused by vibrations of atoms and molecules
<u>Explanation :</u>
Chemical energy : It is the type of energy in which the potential energy is stored in the bonds between the atoms.
Electrical energy : It is a type of energy in which the electrical charge are moved.
Radiant energy : It is a type of energy in which the electromagnetic energy travels in the waves.
Thermal energy : It is a type of energy in which an internal energy caused by the vibrations of atoms and the molecules.