What is the arrow pointing to? A solution of different molecules. Some of them consist of two small atoms attached to a bigger one. Some are negatively charged, and consist of one big atom attached to a small one. There are also small positively charged atoms, which are pointed at by an arrow. What is the arrow pointing to? A solution of different molecules. Some of them consist of two small atoms attached to a bigger one. Some are negatively charged, and consist of one big atom attached to a small one. There are also small positively charged atoms, which are pointed at by an arrow. water molecule hydroxide ion electron hydronium ion hydrogen ion