Aspartame is a low-calorie artificial sweetener but is not heat-stable. It breaks down at high temperatures, making it unsuitable for cooking or baking. In contrast, sweeteners like sucralose and saccharin are heat-stable and used in baked goods.
\begin{itemize}
\item (1) Correct — Saccharin was the first widely used artificial sweetener.
\item (2) Incorrect — Aspartame is not stable at cooking temperatures.
\item (3) Correct — Alitame is indeed a high-potency sweetener.
\item (4) Correct — Sucralose is a chlorinated derivative of sucrose.
\end{itemize}