Answer:
1. Density can be used to identify a substance
2. Density can be used to ascertain whether a substance will float in water.
Explanation:
The calculation of the density of a substance can be used to identify the substance. If the density of a substance is calculated accurately, and compared with a table of standard densities, then we can identify that substance.
Also, density determines whether an object will float or sink in water. If an object is less dense than water then it will float in water. If it is denser than water, then it will sink in water.
The question is incomplete , complete question is:
Hydrogen, a potential future fuel, can be produced from carbon (from coal) and steam by the following reaction:
Note that the average bond energy for the breaking of a bond in CO2 is 799 kJ/mol. Use average bond energies to calculate ΔH of reaction for this reaction.
Answer:
The ΔH of the reaction is -626 kJ/mol.
Explanation:
We are given with:
ΔH = (Energies required to break bonds on reactant side) - (Energies released on formation of bonds on product side)
The ΔH of the reaction is -626 kJ/mol.
。☆✼★ ━━━━━━━━━━━━━━ ☾
The land breeze arrow is correct
The rest are incorrect.
Warm air should 'rise' by the land
This air then moves towards the sea and cools down
The cool air would then sink
Have A Nice Day ❤
Stay Brainly! ヅ
- Ally ✧
。☆✼★ ━━━━━━━━━━━━━━ ☾
Answer:
Sol is a colloidal suspension with solid particles in a liquid. Foam is formed when many gas particles are trapped in a liquid or solid. Aerosol contains small particles of liquid or solid dispersed in a gas. While solid solution contain solid as solute in either solid, liquid or gas.
Answer:
Electrons in a hydrogen atom must be in one of the allowed energy levels. If an electron is in the first energy level, it must have exactly -13.6 eV of energy.
...
Energy Levels of Electrons.
Energy Level Energy
1 -13.6 eV
2 -3.4 eV
3 -1.51 eV
4 -.85 eV