Ba3PO4 is not neutral, it is positive. (NH4)2SO4 is neutral, the charges cancel.
Mg2OH is not neutral, it is positive. LiF2 is not neutral, it is negative. CaOH is not neutral, it is positive. The answer is (NH4)2SO4, correct ions will have a neutral charge.
The answer is: [B]: "ionic salt" .
___________________________________________________
Note: There is no "sharing of electrons" among the elements in this compound; so this compound in NOT a "covalent molecule".
However, there is ionic bonding: Cu²⁺ and Cl⁻ ; to form: "CuCl₂" .
____________________________________________________
Options if it’s true or false true
M P₂O₅ = 31g×2 + 16g×5 = 142g/mol
1 mole of P₂O₅ contains 5 moles of atoms
5 moles of atoms = 30,01×10²³ a.
142g ----------- 30,01×10²³ a.
0,69g ---------- X
X = (0,69×30,01×10²³)/142
X = 0,14626×10²³ = 1,4626×10²² atoms
:)
B: Painting over a metal surface in order to prevent rust is known as
rust proofing and it works by preventing oxygen and water from reaching
the metal surface thus preventing a redox reaction which would result in
rusting.