Question

Is a chocolate-chip cookie a pure substance (element or compound) or a mixture (homogeneous or heterogeneous)?

1) Pure substance (element)
2) Pure substance (compound)
3) Mixture (homogeneous)
4) Mixture (heterogeneous)

Answer 1

A chocolate-chip cookie is a heterogeneous mixture because it contains multiple ingredients that are not uniformly mixed. Therefore, the correct option is 3.

Step-by-step explanation:

A chocolate-chip cookie is definitely not a pure substance; it is a heterogeneous mixture. A pure substance can either be an element or a compound, both of which have a constant composition throughout. In contrast, a chocolate-chip cookie is made up of multiple components such as flour, sugar, chocolate chips, and butter that are not uniformly distributed throughout the cookie.

Mixtures can be either homogeneous or heterogeneous. A homogeneous mixture has its components evenly spread out throughout the sample, like saltwater, where the salt is evenly distributed within the water. A heterogeneous mixture, like a chocolate-chip cookie, has distinct parts and can be seen as having different phases or sections within it. Therefore, the chocolate chips can be clearly distinguished from the rest of the dough.