Today, we did the molar volume lab. It was a complicated experiment requiring much thought and concentration. With this in mind, we were ready to do the lab. No pressure, right?
Our objective is to find out the ratio of the number of moles of iron used up in our reaction to the number of moles of copper produced in the reaction between iron (in the nails) and Copper (II) chloride. The iron is present in the nails and the Copper (II) chloride is present in the form of a powder. Here's what Copper (II) chloride looks like:
The materials used in this lab include two 400mL beakers, a spray bottle, a stir rod, tongs, lab aprons, goggles, a weigh scale, a drying oven, filter paper, a scoopula, a funnel, a graduated cylinder, and a measuring container.
As mentioned before, this lab was fairly complex. Here's what we had to carry out:
- Take out the scale and gather all your materials. Get a 400 mL beaker and, using a graduated cylinder, measure out about 50 mL of water and put it into the beaker.
- Place your measuring container on the scale, then reset you scale to zero. Add a sample of Copper (II) chloride to the measuring container using the scoopula. About 7-8 grams is needed.
- Dump your sample into the beaker and stir gently with a stir rod.
- Take two nails and measure them on the scale after resetting it to zero. After recording this number, place them into the beaker.
- Wait approximately 15 minutes. Then, using tongs, remove both nails. Using a spray bottle or scoopula, scrape the newly formed copper into the beaker until your nail appears clean.
- Weigh the nails again after drying. Subtract the final mass of the nails from the initial mass to find out how much iron was used up in the reaction.
- Prepare your retort stand/lab clamp, funnel, and another beaker. After placing the funnel in the center of the clamp with the fresh beaker directly below, grab a filter and weigh it. Then, after folding it appropriately, place it in the funnel.
- Pour your solution of Copper (II) chloride into the funnel and allow it time to filter. Be sure to use your stir rode to decant when pouring. After the substance has filtered, you will be left with copper in your filter. Place the filter in the drying oven to dry.
- After drying, weigh the filter again. Subtract the initial weight of the filter from the final weight. This is the mass of copper in the filter.
- Clean up all your materials and safely dispose of all chemicals.
As in every lab, we had observations. They include seeing the copper form on the nail. It had a rust-like appearance. We noticed that it did not hold very strongly to the nail. With just a spray of water, most of it came off. We also saw the copper (II) chloride dissolve in the water and form a bright turquoise colour. Another observation was the solution becoming a darker shade after it had reacted with the nail.
We carried out experiment within 8% accuracy. We made many qualitative measurements in the experiment. For example, the mass of our filter paper after filtration was 2.36g.
We concluded our lab by stating possible reasons of error. One possible reason for the error is pouring too much water above the filter. This caused the copper to leak through the sides. Not too much copper would have passed through though, as we exceeded the filter limit by a small amount. Another reason for our error could include not scraping all the copper off. Other mistakes that could have possibly accounted for the error took place when using the tongs. The tongs could have scraped off and lost some of our copper while we were removing it from the nails.
A similar experiment can be seen here:
Posted by Andrew.
No comments:
Post a Comment