B
mass of solute - 4.0 g
mass of solution - 100g + 4.0g = 104g
4/104 = 0.03846
0.03846 • 100 = 3.8%
Answer is (2) - hydrogen carbonate
<em>Explanation:</em>
NaHCO₃ is an ionic compound which is made from Na⁺ and HCO₃⁻ ions. The decomposition is
NaHCO₃ → Na⁺ + HCO₃⁻
Among the resulted ions, Na⁺ is a monatomic ion while HCO₃⁻ is a polyatomic ion.
<em>Polyatomic ions mean ions which are made of two or more different atoms.</em>
HCO₃⁻ is made from 3 atoms as H, C and O. The name of HCO₃⁻ ion is bicarbonate or hydrogen carbonate.
Accuracy is more of a range
A.) Hydroxide ion is the negative ion found in bases.
C.) Color change occurs during neutralization reaction.
Hope this helps!
