Question: Antacids are compounds that neutralize stomach acid. Write the equation that shows how Milk of Magnesia, Alka-Seltzer, and Tums remove excess acid.

1. Milk of Magnesia:
2. Alka-Seltzer: and
3. Tums:

Antacids are medicines that are used to maintain the PH of your stomach. It neutralizes stomach acidity by undergoing a neutralization reaction with the acids present in your stomach and thus saves you from heat burn or indigestion.

It works as a buffer that neutralizes the acids present.

a. Subpart (a)
$\mathrm{Mg}\left(\mathrm{OH}\right)+2\mathrm{HCI}\to {\mathrm{MgCI}}_2+2{\mathrm{H}}_2\mathrm{O}$

It is a neutralization reaction occurring between the hydroxide ion in Milk of Magnesia and the stomach acids.

b. Subpart (b)

$KHC{O}_{\mathit{3}}\mathit{+}HCI\to \mathrm{KCl}+{\mathrm{CO}}_2+{\mathrm{H}}_2\mathrm{O}$

${\mathrm{NaHCO}}_3+\mathrm{HCI}\to \mathrm{NaCI}+{\mathrm{CO}}_2+{\mathrm{H}}_2\mathrm{O}$

Alka-Seltzer is a metal carbonate that reacts with the excess acid and neutralizes it by forming carbon dioxide and water.

c. Subpart (c)
${\mathrm{CaCO}}_3+2\mathrm{HCI}\to {\mathrm{CaCl}}_2+{\mathrm{CO}}_2+{\mathrm{H}}_2\mathrm{O}$
Tums or calcium carbonate plays a significant role as antacid. It undergoes neutralization reaction with the excess acid forming carbon dioxide and water.