Based on the electron configuration of the two atoms, predict the ratio of metal cationic (+) atom
to nonmetal anionic (-) atom in the compound.
Sodium 1s22s22p63s1
Bromine 1s22s22p63s23p64s23d104p5
A. 1:1
B. 1:2
C. 2:1
D. 3:1

It's option B, 1:2

Explanation:

I have the same problem, and it was marked correct when I clicked on option B.

in the given question, the partial pressure is calculated by using the ideal gas equation, that is, pv = nrt

here, p is pressure, v is volume = 25 l, n is number of moles = 0.0104 moles, r is gas constant = -0.0821 l.atm / mol.k

t is temperature = 273 k

p = nrt / v

p = (0.0104 mol × 0.0821 l.atm / mol.k × 273 k) / 25 l

= 0.0093 atm

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.