In a mixture of alcohol and water the two liquids cannot be seen separately while in a mixture of oil and water, both the liquids can be seen separately. Why?

Explanation

Alcohol and water are miscible in each other hence, they form a homogeneous mixture. Since, they mix into each other so they cannot be seen separately. Oil and water are immiscible liquids, hence, they form a heterogeneous mixture. Since, they do not mix into each other and form separate layers so they can be seen separately.