R was 16 months old at the time of this activity
We had some experimenting fun today! I put a few drops of food colouring at the bottom of six small plastic cups (a different colour in each cup). I then added a scoop of baking soda to each cup. I gave R a squeeze bottle (an empty bottle of sriracha sauce since that’s what I had on hand – or you can use painting bottles that I had used for subsequent activity here) filled with vinegar and she worked her hand muscles as she squeezed the liquid into the cups. She squealed with delight as the chemical reaction between the baking soda and vinegar caused the food colouring to come bubbling up. When she emptied the bottle of vinegar, she began mixing the colours together and the bubbling continued on. She absolutely loved this activity!!
This is definitely a messy activity, so have some towels on hand to soak up all the liquid. I did this activity with R seated in her high chair so that I could easily clean up afterwards with R out of the way. If you are concerned about the mess, it’s just as fun to do the activity outdoors!
a. Art Project. I saw this extension idea put out by Misty over at Motley Toddler and had to share it! Place the food colouring and baking soda onto one tray instead of separate cups. Have the child add vinegar using a medicine dropper to make more contained eruptions. Once the colourful eruptions subside, place a piece of construction paper or water-colour paper on top to create printed paper.
b. Scientific Testing. With an older child, explore what happens with vinegar is combined with other household powders (such as baking powder or corn starch). Have him/her record his/her observations in a science journal.