# Why is t-butyl alcohol soluble in water?

What is the similarity between ${\left({H}_{3} C\right)}_{3} C O H$ and $H O H$? The hydroxyl group?
Clearly, $\text{tert-butanol}$ has some similarity with the water molecule. And that similarity is the hydroxyl group. You should look up the aqueous solubility. It would not be immiscible; by the same reasoning it would not be infinitely miscible, as is methanol and ethanol.
A good comparison would be the solubility of $\text{n-butanol}$ and $\text{sec-butanol}$ in aqueous solution. As a prediction, which certainly might be mistaken, $\text{tert-butanol}$, might be more soluble than $\text{n-butanol}$, but as chemists, as physical scientists, we should always seek out the data to inform our arguments, and never the other way round.