difference between physical change and chemical change

Carbon dioxide is already dissolved in the carbonated water (hence the name) and shaking the closed bottle causes pressure to build up inside. Part 5 seems like it might be a chemical change as well, since bubbles are produced, but actually this is a physical change. The bubbles observed are due to carbon dioxide escaping.

When you mix the two, they react to form gaseous carbon dioxide. Vinegar is acidic and baking soda is basic. These milk currents carry the food colouring with them, which is why we witness the colours spreading out. The soap breaks the surface tension of the milk, which causes currents. Part 3 is a physical reaction as well, though it may not look like it. As the solution dries up, however, the sugar will reappear unchanged. Substances that are small and light enough can dissolve in water, and remain suspended between the water molecules, so that it seems they have disappeared. The rust on the penny reacts with the vinegar, which is why it gets removed from the penny.

In a physical change, the material itself is the same before and after the change, although some extensive properties (like shape, phase, etc.) of the material changes. Common indications of chemical changes are colour change, bubbles, the formation of a new substance or the emission of a gas. While introducing the activity, it would be useful to remind students that chemical changes involve processes in which the substances present at the beginning of the change are not present at the end and new substances are formed. The reason for this is because in this activity, the students are asked to draw upon their knowledge of the changes, and to determine which of the processes are physical and which are chemical. This activity is best done towards the end of your unit on physical and chemical changes. 3 Deep set plates / pans (for the milk, vinegar, and soda water).Through their observations, students will note the differences between these processes and use their understanding of these differences to classify five different processes as chemical or physical. In this activity, students will experience physical and chemical changes.

Difference between physical change and chemical change