Answer:
See explanation
Explanation:
9) If an extra electron is added to the neon atom, then the electronic configuration becomes; 1s2 2s2 2p6 3s1
This last electron has quantum numbers;
n=3, l=0, m=0 and s = +1/2
This is so because the 2s level is already filled so the extra electron must go into the 3s level. The orbital quantum number and the magnetic quantum number for the s orbital is zero.
10) Electron affinity is the energy released when one mole of gaseous atoms accept one mole of gaseous electrons to form one mole of gaseous ions having a negative charge.
In the second period, fluorine has the greatest electron affinity since electron affinity increases across the period. The noble gas, neon has an electron affinity of 0KJ/mol.
11) Ionization energy decreases down the group but increases across the period due to increase in the size of the nuclear charge and decrease in the distance between the nucleus and the outermost electron. Hence, the process; Br+(g) ---->Br2+(g) + e- has the greatest ionization energy. Recall that the second ionization is always higher than the first ionization energy.
12)The order of decreasing metallic character here is K> As> P. Even though As and P belong to the same group, we must note that metallic character increases down the group hence the order written above.
Because ecosystems don't change over one day, they change over a long period of time. Plus, something that happens may be because of more than just one change.
NaH(s)+ H2O (l)=>NaOH(aq)+H2(g)
You want to calculate the mass of NaH, I assume. Otherwise, the question isn't clear. It simply says calculate the mass(??)
So, calculate the moles of H2 gas that satisfy the conditions of 982 ml at 28ºC and 765 torr. But you must subtract the vapor pressure of water at 28º to get the actual pressure of the H2 gas. So, the actual conditions are 982 ml (0.982 L) and 301 K and 765-28 = 737 torr.
PV = nRT
n = PV/RT = (737 torr)(0.982 L)/(62.4 L-torr/Kmol)(301 K)
n = 0.0385 moles H2
moles NaH needed = 0.0385 moles H2 x 1 mole NaH/mole H2 = 0.0385 moles NaH required
mass of NaH needed = 0.0385 moles x 24 g/mole = 0.925 g NaH
Brainliest Please :)
