Answer:
ΔH = - 44.0kJ
Explanation:
H2O(l)→H2O(g), ΔH =44.0kJ
In the reaction above, liquid water changes to gaseous water. This occurs through a process known as boiling. This process requires heat, hence the ΔH is positive.
If he reaction is reversed, we have;
H2O(g)→H2O(l)
In this reaction, gaseous water changes to liquid water. This process is known as condensation. The water vapor loses heat in this reaction. Hence ΔH would be negative but still have the same value.
Answer:
210 grams should be correct
Explanation:
hope this helps
Answer:
The valency does not change going down a group since the bonding behavior is not affected by the core electrons.
The color of the light depends on the element to which it interacts. On interacting with energy, the electrons goes to the higher excitation state and when electron drops to lower state which is more stable, the energy is re-emitted as light. Each element produces its own characteristic color.
In case of a sodium street lamp, more photons in the long wavelength are emitted by the sodium gas, leading to yellow color one see. Whereas in case of a neon light, the neon gas is a noble gas, stable and non-reactive. The electrons in neon will excite on applying current. The free electrons will collide with each other and then return back to the atoms. The energy is produced in the form of light on absorbing electrons by the atoms. This falls in the red region of spectrum and thus emits red color.
Answer:
oxygen . 1 percent and 4 percent the are the awnsers