Answer:
Among Na ,K , Pb , Li , The atom which does not react with water is :
<u>Pb</u>
Explanation:
Li : Reacts slowly with water
Na ,K : Reacts vigorously with water
Pb : It does not reacts with water because :- Pb oxidize in presence of atmospheric oxygen to form lead oxide (PbO) . this PbO form a layer over the surface of Pb and make it inert to water.
From electronic configuration valence electron of Nitrogen is 5, oxygen 6x2 which 12 since it involve two molecules , that of is frulorine is 7, and that No2F is 24 which is gotten form adding (5,12,7 ).All resonance structure are as follows
F
.. I ..
: O : N :O:
..
OR : F:
I
N .. : F:
/ \ or I
.. .. N
:O : :O: / / \\
/ / \\
:O : : O:
Answer:
3.82 x 10²¹ molecules As₂O₃
Explanation:
To find the amount of molecules arsenic (III) oxide (As₂O₃), you need to (1) convert kg to lbs, then (2) convert g As₂O₃ to moles As₂O₃ (via molar mass), and then (3) convert moles to molecules (via Avogadro's number).
1 kilogram = 2.2 lb
Molar Mass (As₂O₃): 2(74.992 g/mol) + 3(15.998 g/mol)
Molar Mass (As₂O₃): 197.978 g/mol
Avogadro's Number:
6.022 x 10²³ molecules = 1 mole
0.0146 g As₂O₃ 1 kg 189 lb
------------------------ x --------------- x ------------------ x ................
1 kg 2.2 lb
1 mole 6.022 x 10²³ molecules
x ------------------ x --------------------------------------- = 3.82 x 10²¹ molecules As₂O₃
197.978 g 1 mole
6.02214086 x 10^23 mol^-1
