Spring had turned the corner and twins Frances and Fiona were pleased that they could start spending time outside in their backyard. The family's yard was sheltered by trees with long branches, perfect for the girls' hobby of bird watching.
Frances had the job of mixing sugar in water for their hummingbird feeder. In the past, the girls noticed that more hummingbirds came to the feeder when they used a more sugary mix. This year Frances had decided to make the mix as sweet as possible. In the kitchen, she added sugar to hot water until sugar started collecting in the bottom of the pot even while she was stirring it. Then she filled the feeder with the water solution.
"I just love it when we get to see so many hummingbirds!" Frances said as she screwed the lid onto the feeder.
The girls hung the feeder on a tree branch where they could watch from their deck. It took a few days for the hummingbirds to start coming, and when they did, the birds left almost instantly each time.
The girls went out to check the feeder.
"I think I see the problem," Fiona said, scraping powder from the feeding holes.
"Where did that come from?" Frances asked.
"The birds can't get the mix out of the feeder," Fiona said. "This powder clogging the holes is sugar."
"I didn't put any sugar on the outside," Frances protested. "And I stopped adding sugar to the water when the sugar started collecting at the bottom of the water even when I was stirring it. I know that when there's as much sugar as the water can hold, the water is saturated and can't dissolve any more sugar. Isn't that right?"