The pencil attached to the negative terminal of the battery collects hydrogen gas while the one connected to the positive terminal collects oxygen.
The number of valence electrons = group number
e. g 1 valence electron in group IA
<h3>Answer:</h3>
Heterogeneous mixture
<h3>Explanation:</h3>
The easiest way of defining Heterogeneous mixture is that it is mixture in which the composition of components is not uniform. Also, the substances present in this mixture are visible to naked eye. In fact, the size of solutes in heterogeneous mixture is greater as compared to that the sizes of solutes in homogeneous solutions. hence in salad dressing the oil, vinegar and spices are all visible and can easily be seen by naked eye.
