Answer:
4 energy levels/rings
Explanation:
By the atomic model proposed by Niels Bohr, the electrons orbit around the nucleus in shells having different energy level each with the ability to contain a given maximum amount of electrons.
The closest shell to the nucleus named the K shell, can have a maximum of two electrons, the next shell known as the L shell can have 8 electrons while the next shell, M, can have a maximum of 18 electrons
The arrangement of the periodic table is based on the number and location of electrons such that elements in the 4th row (period 4 elements) have three completed energy levels/rings before, their valence ring making the total number of rings = 4 energy levels/rings.
You can split the process in two parts:
1) heating the liquid water from 10.1 °C to 25.0 °C , and
2) vaporization of liquid water at constant temperature of 25.0 °C.
For the first part, you use the formula ΔH = m*Cs*ΔT
ΔH = 30.1g * 4.18 j/(g°C)*(25.0°C - 10.1°C) = 1,874 J
For the second part, you use the formula ΔH = n*ΔHvap
Where n is the number of moles, which is calculated using the mass and the molar mass of the water:
n = mass / [molar mass] = 30.1 g / 18.0 g/mol = 1.67 mol
=> ΔH = 1.67 mol * 44,000 J / mol = 73,480 J
3) The enthalpy change of the process is the sum of both changes:
ΔH total = 1,874 J + 73,480 J = 75,354 J
Answer: 75,354 J
it's either A. or C. because
seaweed having 50 g salt in 1 L water. The bucket contains 150 g of salt in 2 L of water
amount of water present in bucket is twice to amount of water in weed

At equilibrium, volume of water in weed is x and volume in bucket is y but concentration remain same as follows:

At equilibrium, weed loose z L from 1 L water to bucket containing 2 L as follows:

Thus, Weed will loose 0.25 L of water