Silver nitrate precipitate lab

Purpose: Find how much silver is produced from 1g of silver nitrate.
Hypothesis: If silver nitrate is mixed with copper wire, then one gram of silver precipitate will form on the wire.
Materials: Silver nitrate solution, copper wire, distilled water, test tube, beaker, filter paper and small funnel.
Procedure: Pour 1g of silver nitrate solution into the test tube, leaving enough room left for the copper wire. Carefully put on 30cm of copper wire into the test tube and tape over the opening of the tube. Let the wire sit in the solution for 24 hours. Upon return, position the funnel over the opening of the beaker and roll the filter paper to create a cone to catch any precipitate that may have formed from the reaction. Next, carefully remove the tape from the test tube and pour out the excess solution into the filter paper cone. Then, lightly spray the copper wire with distilled water, getting off any precipitate from the wire and into the paper cone. Once all remaining precipitate is in the filter paper, weigh the wire and the precipitate separately.
Conclusions: 0.35g of silver was produced from the reaction and 0.247g of copper was lost. Our original hypothesis was proven wrong, due to a miscalculation in stoichiometric equations which led us to the aproximate result of 1g of precipitate.

Molar calculations

One mole is equal to 6.02 times 10^23. This number was introduced by Amedeo Avogadro to simplify a unit of atoms. An element's atomic weight is how many grams of weight are present in one mole of that atom. Percentages of elements present in a molecule of a substance, such as aluminum chloride, can be found by going through some simple mathematical steps; as shown below:

Popcorn lab

Purpose: find out how much of unpopped popcorn kernals' mass is made up of water.
Hypothesis: When popcorn kernals are popped, atleast one third of the total mass of the kernals will be lost due to loss of water caused by high temperature.
Materials: Glass beaker, vegetable oil, unpopped popcorn kernals, Bunsen burner, and foil.
Procedure: First, weigh the popcorn kernals and record the total weight befor reaction takes place. Next, fill the glass beaker with a small amount of oil to pop the kernals in. Put kernals in the beaker and cover the top with aluminum foil to keep heat inside the beaker. Poke holes in the foil to let pressure from the heated air escape. Then, place the beaker above a bunsen burner so that the flame heats the beaker evenly. Light the flame and wait for the kernals to pop. Then, remove the popped kernals and weigh them and record the difference in weight.
Results: One gram of weight was missing from the kernals.
Conclusion: The original hypothesis of one third of weight being lost from the reaction proved false. Though only a small amount of weight was lost from the lost water from the kernals, it was still apparant that the weight difference was caused by evaporated water trapped in the kernals. Based on the original weight of 6.5g of the kernals and the loss of 1g from teh experiment, it can be calculated that about 15.38% of the unpopped kernals' weight comprised of water.

Metal Reaction Lab

Hypothesis: Some metals will be more reactive than other metals, due to their atomic configuration.

Materials: Copper (II) nitrate, magnesium nitrate, zinc nitrate, silver nitrate, copper grains, magnesium ribbon, zinc granules, pipets, and a 24 well plate.

Procedure: First, we added small amounts of copper (II) nitrate, magnesium nitrate, zinc nitrate, and silver nitrate to 3 seperate wells each in the 24 well plate. Thats 3 wells for each mixture. For each of the 3 wells that we gave the separate mixtures, we mixed in one with copper grains, one with a small piece of magnesium ribbon, and one with zinc granules. After each of the metals was mixed with the 3 separate solutions, we waited about 5 minutes to observe any reactions.

Copper on reacted with the silver nitrate; producing a precipitate. All of the other solutions had little to no visible reaction with the copper grains.
Magnesium had almost the opposite effect, which reacted with every solution except for the magnesium nitrate.
Zinc reacted with the copper (II) nitrate and silver nitrate solutions, but not with the zinc nitrate nor the magnesium nitrate.

Conclusion: Our hypothesis was correct to an extent. We were right in the aspect that some metals are more reactive than others. Magneium was very reactive to the solutions while copper (II) was not so very reactive. We didn't specify which metals would react more, but we got our results. In reactivity (from most to least), the metals used ranked magnesium, zinc, then copper (II).

Periodic Table

The periodic table of elements is a way of organizing the chemical elements in periods and groups according to their properties. For example: a highly reactive element can be found on the table next to another highly reactive element. These are called halogens, but we'll get to those later. The periodic table goes from left to right in periods according to the number of protons in the nucleus of an atom of that element. As you move from left to right in a period, the number of protons from element to element increases.
This is all well and good, but what about conductivity or reactivity? Well, as you reach the end of a period, the number of valence electrons (electrons in the outer electron shell of that element's atom" increases.What does this mean? Well, when an atom's outer electron shell is full, that means that is not very reactive. When the outer shell of an atom is filled all the way, it is called a noble gas. These are the least reactive of the elements. Right to the left of those are the halogens, highly reactive elements. They are so reactive due to the fact that their outer electron shells are not filled to the maximum, but by just barely. This means that another element's atom with an electron to fill that gap in the halogen's electron cloud can react with it so easily.

Spectra Lab

Using spectrascopes, we looked at different light filters and what lights they emit. When we looked through these special devices through the right angle, we could see the different colors in the visible light spectrum emitted by different properties.

This artist's representation of what was viewed through the spectrascope show what colors are given off. The first of this set was a normal, white light which showed each of the 7 colors (red, orange, yellow, green, blue, indigo and violet). But, as the lights change, different colors are emitted. When a red fluid is placed in front of the light bulb and viewed through the spectrascope, the red part of the spectrum is larger. When a light blue fluid is put in front of the light instead, there is no orange light reflected. When gasses and other materials were put into a bulb and shown, we examined each of them with the spectrascopes. When examining a bulb with hydrogen in it, the only colors that were shown were red, blue and violet. When we used a mercury bulb, only orange, green and violet were visible. When argon was used, red and orange were very faint when viewed through the spectrascope. However, green and violet (the only other 2 colors present) were clearly seen. When a neon bulb was observed, there was a black line in between orang and green, replacing yellow. There was also little to no indigo or violet light seen. When a nitrogen bulb was observed, the full spectrum of colors was visible. The only odd thing was the two black lines in the green area of the spectrum. When observing iodine, all colors were very faint and there were black lines on both sides of the blue area. Helium reflected all of the colors except for violet and had black lines before and after the orange area.

This experiment shows that different gasses and elements reflect and absorb different parts of the visible light spectrum. It gives us better understanding of the energies emitted by what colors are absorbed or reflected.

Atomic Structure

An atom, the smallest particle of an element that still retains the properties of that element, can be split up into smaller particles. Even long ago, they conceived that the atom could be divided into smaller parts. The problem was that they did not know exactly how they were split up. The ancient Greek philosopher, Democritus, thought that atoms were the smallest form of matter and were , therefore, indivisible. A man named John Dalton also believed atoms to be indivisible. Dalton also believed that atoms could not be created or destroyed.

As the question of how atoms are composed has ben risen many many times; so much that people have tried to explain how atoms look. A man named J.J. Thomson made a "plum pudding" model of what an atom looks like:

As you can see, the positive particles (protons) and the negative particles (electrons) are randomly spread out in the atomic space. Thomson was on the right track, but no cigar. A more accurate model was produced by a man named Ernest Rutherford:

Rutherford proposed that the negatively charged electrons orbited around a positively charged nucleus. While this is very very close, what's missing from this picture? Figure it out? That's right; there are not neutrons in the nucleus.

That's better. The orange, uncharged particles in the nucleus that are with the protons are the neutrons. They have no charge, but they add to the atomic mass of the atom. An atom of an element is characterized by its mass number and its atomic number. The mass number is the average mass of the most commonly found isotopes of an element found in nature. Isotopes are atoms of the same element with a different amount of neutrons. The atomic number is the number of the number of protons in the atom of that element. If two atoms have a different number of protons, they are atoms of different elements. If they have the same amount of protons, but different amount of neutrons, they're isotopes.