Lambda = h\ Mv
lambda = 6.624 x 10^-34 / 9.1 x 10^-31 x 2.5 x 10^7
lambda = 2.9 x 10^-11 is your wavelength
The correct option is D. 2) Anti-bonding electrons or lone pairs. These lone pairs, and bonds helps to form the shape which keeps these electrons separate as possible.
What happens is it makes water
Molar mass H₂O = 18.0 g/mol
number of moles :
1.0 / 18.0 => 0.055 moles
1 mole -------------- 6.02 x 10²³ molecules
0.055 moles -------- ? molecules
molecules = 0.055 x ( 6.02 x 10²³) / 1
molecules = 3.311x10²² / 1
= 3.311 x 10²² molecules
hope this helps!