Why is a cake not mixture?

Here's why:

* Mixtures are combinations of two or more substances that are not chemically bonded. A cake is made from flour, sugar, eggs, butter, and other ingredients that are not chemically combined. They are simply blended together.

* The components of a mixture retain their individual properties. You can still identify the flour, sugar, and other ingredients in a cake.

* Mixtures can be separated by physical means. You could potentially separate the sugar from the flour in a cake by using a sieve or other methods.

So, while the ingredients in a cake undergo chemical changes during baking (like the browning of the flour), the cake itself is still considered a mixture because the individual components aren't chemically bonded.