A. K+, OH-
B. C6H5CO+, OH-
C. NH4+, Cl-
D. Mg++, 2 NO3-
Everything has 1 except for the Nitrate ion in D, which has 2
Answer:

Explanation:
The expression can be solved mathematically as follows:
1)
Given
2)
Definition of sum
3)
/Associative property
4)
Distributive property
5)
Multiplication
6)
Subtraction.
7)
Multiplication/Associative property
8)
Associative property
9)
/Result
Explanation:An ionic bond essentially donates an electron to the other atom participating in the bond, while electrons in a covalent bond are shared equally between the atoms. The only pure covalent bonds occur between identical atoms. ... Ionic bonds form between a metal and a nonmetal. Covalent bonds form between two nonmetals.
Answer:
731.25 g
Explanation:
The question asks us to calculate the mass of 12.5 moles of NaCl. The individual relative atomic masses of the elements were supplied. We must first obtain the molar mass of sodium chloride as follows;
Molar mass of sodium chloride= 23.0 + 35.5 = 58.5 gmol-1
From the formula;
Number of moles (n) = mass /molar mass
Number of moles of sodium chloride= 12.5 moles
Mass of sodium = The unknown
Molar mass of sodium chloride= 58.5gmol-1
Mass of sodium chloride= number of moles × molar mass
Mass of sodium chloride= 12.5 × 58.5
Mass of sodium chloride= 731.25 g