1. The reactivity among the alkali metals increases as you go down the group due to the decrease in the effective nuclear charge from the increased shielding by the greater number of electrons. The greater the atomic number, the weaker the hold on the valence electron the nucleus has, and the more easily the element can lose the electron. Conversely, the lower the atomic number, the greater pull the nucleus has on the valence electron, and the less readily would the element be able to lose the electron (relatively speaking). Thus, in the first set comprising group I elements, sodium (Na) would be the least likely to lose its valence electron (and, for that matter, its core electrons).
2. The elements in this set are the group II alkaline earth metals, and they follow the same trend as the alkali metals. Of the elements here, beryllium (Be) would have the highest effective nuclear charge, and so it would be the least likely to lose its valence electrons. In fact, beryllium has a tendency not to lose (or gain) electrons, i.e., ionize, at all; it is unique among its congeners in that it tends to form covalent bonds.
3. While the alkali and alkaline earth metals would lose electrons to attain a noble gas configuration, the group VIIA halogens, as we have here, would need to gain a valence electron for an full octet. The trends in the group I and II elements are turned on their head for the halogens: The smaller the atomic number, the less shielding, and so the greater the pull by the nucleus to gain a valence electron. And as the atomic number increases (such as when you go down the group), the more shielding there is, the weaker the effective nuclear charge, and the lesser the tendency to gain a valence electron. Bromine (Br) has the largest atomic number among the halogens in this set, so an electron would feel the smallest pull from a bromine atom; bromine would thus be the least likely here to gain a valence electron.
4. The pattern for the elements in this set (the group VI chalcogens) generally follows that of the halogens. The greater the atomic number, the weaker the pull of the nucleus, and so the lesser the tendency to gain electrons. Tellurium (Te) has the highest atomic number among the elements in the set, and so it would be the least likely to gain electrons.
Answer:
the amounts and compositions of the overflow V1 and underflow L1 leaving the stage are 75kg and 125kg respectively.
Explanation:
Let state the given parameters;
Let A= solvent (hexane)
B= solid(inert soiid)
C= solvent(oil)
= mass of solvent + mass of oil (i.e A+C)
<u>Feed Phase:</u>
Total feed (i.e slurry of flakes soybeans)= 100kg
B= mass of solid =75 kg
F= mass of solvent + mass of oil (i.e A+C)
= 25kg
Mass ratio of oil to solution 
=
mass of oil (C) =25 × 0.1 wt = 2.5kg
mass of hexane in feed = 25 × 0.9 =22.5kg + 2.5 =25kg
therefore = 
= 0.1
mass ratio of solid to solution 
= ![\frac{Mass A}{Mass (A+C)}=[tex]\frac{75}{25}](https://tex.z-dn.net/?f=%5Cfrac%7BMass%20A%7D%7BMass%20%28A%2BC%29%7D%3C%2Fp%3E%3Cp%3E%3D%5Btex%5D%5Cfrac%7B75%7D%7B25%7D)
=3
<u>Solvent Phase:</u>
C= Mass of oil= 0(kg)
A= Mass of hexane = 100kg
mass of solutions = A+C = 0+100kg
solvent= 100kg
<u>Underflow:</u>
underflow = L₁ = (unknown) ???
L₁ = E₁ + B
the value of N for the outlet and underflow is 1.5 kg
i.e N₁ = 
solution in underflow E₁ = Mass (A+C)
<u>Overflow:</u>
Overflow = V₁ = (unknown) ???
solution in overflow V₁ = Mass (A+C)
This is because, B = 0 in overflow
Solid Balance: (since the solid is inert, then is said to be same in feed & underflow).
solid in feed = solid in underflow = 75
75= E₁ × N₁
75 = E₁ × 1.5
E₁ = 50kg
Underflow L₁ = E₁ × B
= 50 + 75
=125kg
The Overall Balance: Feed + Solvent = underflow + overflow
100 + 100 = 125 + V₁
V₁ = 75kg
Latent heat, also called the heat of vaporization, is the amount of energy necessary to change a liquid to a vapour at constant temperature and pressure. The energy required to melt a solid to a liquid is called the heat of fusion
Radiation is the heat that travels directly to the earth
