How Much Sugar is in Sugar Cane

The following is a summary of the procedure that a student completed on her own. In her procedure she tried to make sugar from sugar cane. I talked about this experiment in an earlier blog (see below).

The Question
For my experiment I chose to find the amount of water and sugar in 40 grams of sugar cane.

What worked well in my Experiment
Before I could even start my experiment, I needed to find sugar cane. Looking for it in China Town was a good idea. Then when I got the cane, I needed to find a way to shred it (to increase the surface area so contained sugar would dissolve faster). To do this I chopped up the cane into bite sized pieces and then put it in a food processor. This worked great!

What didn’t work well in my Experiment
A couple things went wrong that affected my results. The first thing was the fact that a lot of water was retained in my residue when I filtered and the mass of the water was included in the weight of my residue which made it impossible to find the actual amount of water in 40 grams of sugar cane. The second thing that went wrong was I forgot to measure the beaker that held the pure sugar when it was empty. Since the masses of different beakers vary, when I weighed the beaker filled with sugar I had to subtract the average mass of a 400 ml beaker instead of the mass of the beaker I was using.
Another thing that didn’t go well was that I burnt my sugar due to evaporating my water at too high a temperature.

What I would change if I did this again

If I did my experiment again I would make sure I measured my residue when it was dry and again when it was wet. I would also make sure to remember which beaker weighed what and if I had measured them all while they were empty. The final thing I would change was the temperature at which I evaporated all my water. Instead of 100 °C, I would evaporate at 70 °C or 60°C.

Here is the new and improved procedure for determining the amount of sugar and water in sugar cane:

1. Safety goggles over eyes.
2. Collect all apparatus needed.
3. Measure 200 ml of water using a graduated cylinder
4. Weigh the empty 400 ml beaker
5. Put water in the 400 ml beaker and place on the hot plate. Turn setting to 100 ° C.
6. Weigh 40 grams of pre-shredded sugar cane using a triple-beam balance, a 400 ml beaker and the Dilyara Process.
7. Add the 40 grams of pre-shredded sugar cane to the 400 ml beaker of water. Weigh mixture.
8. Stir gently for 2-3 minutes with a glass rod.
9. Filter mixture using a retort stand, a retort ring, a funnel, filter paper and 400 ml catch beaker.
10. Weigh residue when it’s wet and then later when it’s dry. Subtract the two masses. (Use the Dilyara process when weighing)
11. Collect filtrate and put back on the hot plate. Turn setting to six. Leave it there until all water has evaporated and turn off the hot plate.
12. Collect remaining sugar.
13. Measure using a triple-beam balance and Dilyara process.
14. You now have the amount of sugar 40 grams of sugar cane contains. Take the weight of the mixture in step 6 and subtract the amount of original water, the difference between the dry and wet residue and the mass of the 400 ml beaker from this amount.
15. Then subtract the amount of sugar and the mass of the dry residue from this amount. Your answer is the amount of water in 40 grams of sugar cane.
15. Clean up and put away safety goggles.


Materials
-triple-beam balance
-safety goggles
-graduated cylinder
-400 ml beakers x 3
-hot plate
-40 grams pre-shredded sugar cane
-glass rod
-retort stand
-retort ring
-funnel
-filter paper

Conclusion
A 40 gram sample of sugar cane contains about 3 grams of sugar, about 1 gram of water and the rest is fibers.

Wolf Centre - Haliburton Forest

If you are coming on the Haliburton Trip I thought I should include a picture of one of the highlights we are going to see.

We will be staying at Haliburton Forest where the Wolf Centre is. This is a picture of two of the 8 wolves that live within the 55 acre enclosure. These wolves are not pets and are wild animals however they are used for research as part of the Haliburton Forest Wolf Centre. The research is non-invasive and has much to do with understanding the dynamics of wolf behaviour.

I can hardly wait for the trip to take place. I want to show the students that I am taking there how wonderful the forest is and how much there is to learn from it. Only 3 weeks away now.

The Sweetest Thing

Today another student is trying to separate sugar from its natural form. A dedicated student worked tirelessly to shred sugar beets so that she could use them as the base for her experiment. She then boiled them in water on a hot plate for 10 minutes to get the sugar to go into solution in the water. After we (her and I) tried a variety of methods to filter the mixture of sugar beets and water/sugar solution. We settled on using coffee filters instead of regular filter paper as the regular filter paper kept getting clogged with shredded sugar beets. After filtering the mixture the sugar/water solution was put on a hot plate to boil. We decided a lower temperature was better than the higher as sugar tends to caramelize and become a sticky mess in the bottom of the beaker. As the solution boiled, the water evaporated and the room began to smell like cheap hot dogs.

Now, if you go back over the above paragraph, you will notice the absence of any mention of adding hot dogs, or hot dog extract to the mixture. It has got me completely baffled as to what that smell is. I like cheap hot dogs but is there sugar beets in cheap hot dogs or did we discover the smell that is made when you cook them comes from sugar beets?

Anyway, the procedure is not finished yet and so currently a lukewarm concentrated sugar solution sits in a beaker on my lab desk, patiently waiting for the science lab to open and for this student to come finish her work. This procedure is part of a series of independent experiments that my students have created as a summative project for their Pure Substances and Mixtures unit for Grade 7.

Since switching from cook-book type labs (recipes really) to self-directed student created labs I have noticed a difference in my students. They seem more connected to the science we are doing and that makes me happy. Maybe from this group I will encourage more into the research side of science. Only time will tell, and sadly, I will never know what happens to them. As they graduate from my school they also graduate out of my life. (Sniff, sniff)

Stock Car Challenges

Grade 8's to finish building stock car racers this week and start racing them next week. I was surfing looking for ideas and came across the F1 in Schools website. I wanted to make F1 race cars but the idea of using CO2 canisters on a straight track with a pointy end made me rethink the idea. I'd like to do it sometime but maybe with an older age group.

My students have been working to complete their designs of stock cars they are building from Basswood. We are doing this project as part of the Energy and Control unit of the Ontario Science and Technology curriculum. The topic for the curriculum is Optics but since that is being phased out this year and next I thought I should give my students their best chance at understanding grade 9 electricity unit, which is loosely related to Optics through energy. To start the project I gave them a battery, a light bulb and some wire and asked them to make the light light. I hoped they would have no problem figuring out how to make a circuit go but they did. Some had some incling, others no idea and still others just did not even try. These ones have just given up entirely and we are three weeks from the start of June. After that we have another three weeks. What is sad is that they prefer to spoil it for others and try to do as little work as possible. They just sit back and wait for the work to be done and then tell me how it was their idea etc. Do they think I am really that dumb?

Maybe I am ready for a break.

Solar Oven Challenge and Sugar-Making

Today we made the ovens. The kids were so in to the challenge and they took to it so well. To start they had to design and build their ovens out of recycled materials and insulate them against heat loss. They used black paper, old towels to attract the sun's energy to the ovens and then used recycled chip bags to reflect the sun's energy inside the oven. The top surface had to allow light inside so most used a clear plastic top that they taped to the box.

Inside our ovens we cooked chocolate chip cookies. What was fantastic was that the students measured the temperature inside the boxes and were blown away that they got up to 70 degrees celsius inside. It was also awesome to see that they were really into it and it wasn't just for the cookies. Well, okay, maybe it was.

Another awesome project happened after school. A student of mine is just wrapping her self-directed experiment. She may be posting her comment to the blog later but I will give you the highlights. She took sugar cane, boiled it to get a sugar water solution and then evaporated the water out to make brown sugar. We may have cooked it a little hot because it sort of burnt more than we were expecting but it was awesome. I'm so proud of the science that is going on in my classroom. These kids are really into it. I think I love my job again. (There were darker times before that made me question this so I am happy to say them times are over!)

Science is cool!

Here's to posting more regularly than last year!

Today in Science: Today in my science classes I did something I did not think I could do. I made ice cream without the use of a freezer. I mixed salt with ice cubes to lower the freezing point of ice and then used the liquid cream as a heat source to warm it up. What I mean is that I took the heat out of the cream and put it into the ice/salt mixture. In the process I made the liquid cream freeze into ice cream and hooked my students into heat transfer.

I also highlighted that we would be making a solar oven over the next few weeks and use it to cook food. I think I will make cookie dough while they build their ovens and then allow them to cook the dough and eat the results. In case you are not aware I am teaching grade 7's and we are in the heat and thermal energy unit. I like this unit. My goal for this year was to push critical thinking and problem solving skills. I think my students are doing a wonderful job with it.

For the Grade 8's today we looked at how to move energy from one place to another. We did this by using a battery (AA), two wires, a light bulb and three elastics to start. The challenge was to make the lightbulb light up. I gave very little instruction but circulated looking for the bulb to glow. Some got it right off the bat and some took a little longer. I had them draw a diagram of the circuit and then I added another level to it. I gave them a piece of cardstock, two brass fasteners and a paper clip and asked them to make a switch to turn the lightbulb on and off. The goal with these students is to get them to build a stock car out of pop-cans and power it with a motor. The motor will run off a battery and a switch will turn it on and off. It is part of the optics unit but really I am using it as a testing ground for the grade 8 program I will run next year. This year I had one major building project for the 8's and next year I want to run a few of them.

I do not want to give away too much and that is all that happened today in Science.