SG/Chem blog 4

To all Over the last week in sustainable green chemistry, we continued our studies of mass density and volume. We also did a lab about the density of gas. 

Part 1: density, mass, and volume 

To continue our studies, we worked with our groups on a couple of worksheets. These worksheets gave examples of different ways to solve for mass or volume. One way we were shown, was to multiply the given variable by the equation for the density of the material (g/mL). If we were given a value that was of mass, the equation for density would be flipped, for example:

    g x mL / g =___   or   mL x g/ML =___

We used these equations to help solve a few word problems. My favorite word problem was about a woman whose cheapskate boyfriend got her a ring and said it was 24 carat gold, the question asked us to determine if the ring was real, or if she should dump her dewdbeat boyfriend. In the end, their relationships ended tragically. 

Overall, I really enjoyed this part of our week. It was a lot of fun and I feel like I learned a lot.

Part 2: Density of gas?

This week we did a lab that addressed the question of "how dense is gas?"

Our lab setup included a bin filled with water, a small jar with a tube attached to the top and a bottle filled with water in the bin. The tube from the jar went into the bottom of the bottle. To create the gas to measure, we had alka seltzer tablets .

                    *the experiment*

To answer this question, we first had to find the mass and the volume of the gas. To find the mass, we measured the mass of the jar filled with 40mL of water and the alka seltzer. Then we measured the mass of the jar after the alka seltzer dissolved and found the difference. The difference was the mass of the gas that escaped when the alka seltzer dissolved. To find the volume, we let the gas flow through the tube and into the bottle, once inside, the gas began to displace the water that willed the bottle. We then looked at how much water had been displaced. 

With our volume and mass calculated, we only had one more step. The last step was to calculate the density  (g/mL), we found that the density was around 0.002 (g/mL). That means that gas is around 500 times less dense  than water.

I enjoyed this lab, it was very interesting to learn about how dense gas is. I think it is also important to learn how to calculate the density of gas.

Part 3: Conclusion

Overall, it was a good week in SG/Chem. I had lots of fun and I think that I learned a few new things. The things that I learned include:

- New ways the solve for mass/volume, and how to use that knowledge in word problems

- the density of gas, and how to find the density of gas