25.9 kJ/mol. (3 sig. fig. as in the heat capacity.)
<h3>Explanation</h3>
The process:
.
How many moles of this process?
Relative atomic mass from a modern periodic table:
- K: 39.098;
- N: 14.007;
- O: 15.999.
Molar mass of 
:
.
Number of moles of the process = Number of moles of dissolved:
.
What's the enthalpy change of this process?
for 
. By convention, the enthalpy change 
measures the energy change for each mole of a process.
.
The heat capacity is the least accurate number in these calculation. It comes with three significant figures. As a result, round the final result to three significant figures. However, make sure you keep at least one additional figure to minimize the risk of rounding errors during the calculation.
Answer:
Iron has 5 unpaired electrons in Fe⁺³ state.
Explanation:
Iron having atomic number 26 has following electronic configuration in neutral state.
Fe = 1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d⁶
When Iron looses three electrons it attains +3 charge with following electronic configuration.
Fe⁺³ = 1s², 2s², 2p⁶, 3s², 3p⁶, 3d⁵
The five electrons in d-orbital exist in unpaired form as,
3(dz)¹, 3d(xz)¹, 3d(yz)¹, 3d(xy)¹, 3(dx²-y²)¹
Answer:
1. light is made up of energy
2. light travels in a straight line
3. the speed of light is exactly 299 792 km per second
4. this is the speed when light is traveling in a vacuum and not obstructed by the atmosphere 5. traveling at the speed of light you could go around the earth seven and a half times in a second
6. light can move super fast super slow and not at all
7. we can use light to weigh Stars
8. we can use light as tweezers
9. bubbles can turn sound into light
10. lasers can make things cold
The pressure of the gas is expected to increase in accordance to Boyle's law.
<h3>What is Boyle's law?</h3>
Boyle's law states that, the volume of a given mass of gas is inversely proportional to its pressure at constant temperature.
By implication, when the piston is lowered and the volume of the gas is decreased, the pressure of the gas is expected to increase in accordance to Boyle's law.
Learn more about Boyle's law: brainly.com/question/1437490
Answer:d
Explanation: over time water evaporates which leaves you with the white crystals mass
