Answer:
Approximately
.
Explanation:
Make use of the molar mass data (
) to calculate the number of moles of molecules in that
of
:
.
Make sure that the equation for this reaction is balanced.
Coefficient of
in this equation:
.
Coefficient of
in this equation:
.
In other words, for every two moles of
that this reaction consumes, two moles of
would be produced.
Equivalently, for every mole of
that this reaction consumes, one mole of
would be produced.
Hence the ratio:
.
Apply this ratio to find the number of moles of
that this reaction would have produced:
.
Answer:
B) the chemicals are gaining energy from the surroundings.
Explanation:
The positive sign of the energy difference in a chemical reaction would indicate that the chemicals are gaining energy from the surroundings. This is what happens in an endothermic reaction.
In an endothermic reaction, heat is absorbed from the surroundings hence the surrounding becomes colder at the end of the changes.
- Here the energy change is assigned a positive value.
- This is because the heat energy level of the final state is higher than that of the initial state.
- So, the difference gives a positive value.
Organic compounds contain carbon
Answer:
H = m c ΔT
89.6 J = (20.0 g) × c × (40.0 - 30.0)°C
Specific heat of iron, c = 89.6 / [20.0 × (40.0 - 30.0)] J/(g°C) = 0.448 J/(g°C)