He arranged them in groups of elements and made sure he put similar properties next to each other in vertical columns
Answer: -
Baking soda having a pH of 9, has the maximum number of hydroxide ions.
Explanation: -
More the pH of a solution, the more basic it is and more the number of hydroxide ions it has.
From the question we find that
baking soda has a pH = 9
milk has a pH = 6
tomato juice has a pH = 3.5
vinegar has a pH = 2
Thus among them baking soda has the highest pH.
So baking soda is the most basic and has the maximum number of hydroxide ions.
The net ionic equation shown is for the reaction of an aqueous mixture of sodium hydroxide and hydrochloric acid.
<h3>What is net ionic equation of a reaction?</h3>
A net ionic equation is an equation of a reaction which only depicts the ions which react to form a product.
In a net ionic equation, the spectator ions are removed.
The net ionic equation shows a reaction between hydrogen ions and hydroxide ions to form water.
Therefore, the net ionic equation shown is for the reaction of an aqueous mixture of sodium hydroxide and hydrochloric acid.
Learn more about net ionic equation at: brainly.com/question/13879496
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