Answer:
-8.64kJ
Explanation:
Based on the reaction:
2 H₂O₂(l) → 2 H₂O(l) + O₂(g) ΔH = -196 kJ
When 2 moles of hydrogen peroxide (H₂O₂) descomposed, there are released -196kJ of energy.
Now, if 3,00g of hydrogen peroxide react, moles are:
3.00g × (1mol / 34.01g) = 0.0882moles H₂O₂
Releasing:
0.0882moles H₂O₂ × (-196kJ / 2mol H₂O₂) = <em>-8.64kJ</em>
Circumpolar constellations stay in the sky. Because of the rotation of the Earth and its orbit around the Sun, we divide the stars and constellations into two groups. Some stars & constellations never rise nor set, and they are called circumpolar.
A: It prevents most reactions from occurring spontaneously.
The answer above is correct.
Explanation:
Sodium Chloride or NaCl is made up of two elements, sodium (or Na) and chlorine (or Cl). A molecule of sodium chloride, NaCl, consists of one atom each of sodium and chlorine. Hence, each molecule of NaCl has 2 atoms total.
Answer:
the heat source must be greater than 100°C
the water must be permitted to evaporate quickly
the system must be sealed and become pressurized above atmospheric pressure
the vapor pressure must be kept below 760 mmHg
Explanation:
A superheated water is a dry form of steam in which hydrogen bonds that strongly binds the molecules of water has been overcome.
Superheated water finds application in a wide range of places. For example they are used for sterilization of clinical equipment.
- To produce steam or superheated water, the temperature of the source must be greater than the boiling temperature and less than the critical temperature at 374°C.
- Since superheated water is steam and steam is water in gaseous form. The water must be made to evaporate more quickly than it should condense back.
- High pressure and sealing the system helps to produce superheated water very fast.
- If the pressure between the vapor is kept low, water will boil faster.
