Ink After Separation : Ink Before Separation

Concept 2.1 Matter consists of chemical elements in pure form and in combinations called compounds

The purpose of this lab was to determine the limiting reactant in a mixture of to soluble salts and the percent composition of each substance in a salt mixture.

There are various techniques to separate a mixture of compounds from each other. One of the commonly used way to isolate compounds from a mixture of two compounds is called extraction. This method of extracting two compounds from each other relies on the different solubility of the compounds in two different solvents.

The composition of a pure substance is constant, and thus pure substances have characteristic physical properties that do not change and this is why we are able to separate each element in this lab experiment. Examples of physical properties that can be used to describe pure substances include solubility, conductivity, magnetism, density, boiling point, and melting point.

12. Place the magnet on the scale to measure the mass of the object. Record the mass in Data Table 5.

The objective of this extraction experiment was to achieve a comprehensive understanding, as well as master the practice, of the technique of separating various individual components of a compound.

This experiment was performed to observe differences in density based on the chemical makeup of an object. Pennies minted before 1982, pennies minted after 1982, and an unknown metal sample was tested to see if there were any differences in their densities. Ten pennies from each category and the metal sample were weighed using a scale to find mass and the displacement method was used to find their volumes. The masses and volumes were then used to calculate the densities of the pennies (D=m/v). The density of the pre-1982 pennies were 8.6 g/mL while the post-1982 pennies were 6.9 g/mL. The metal sample’s density was 1.7 g/mL. Following the experiment we were given the real densities of each item to calculate the percent error with the formula

First students obtained 8 graduated cylinders and labeled them. Each one contained a different ratio of vinegar and water. These graduated cylinders with the liquid were weighed and recorded.Then, students obtained an Alka-Seltzer tablet and recorded its mass. Then one alka-seltzer tablet was dropped into each of the graduated cylinders. Students had to

Using elemental analysis to determine the percent mass composition of each element in a compound is the first step in creating an empirical formula. There are many different types of elemental analysis, but in this experiment gravitational analysis and Beer’s Law are used. Elemental analysis is first used to find the moles of each element, then converted to mass, and then the percent mass of the element in the product is found (2).

The order of steps were determined by which solids did not have to be mixed with water and which solids had to be mixed with water. So the first steps were determined if there were any magnetic materials in the mixture; which the iron filings were. The best first step would have been to separate the large materials from the small materials (the bird seed would be separated from the sand, salt, and iron filings) using a sifter so that all the salt, sand and iron filings can be found easily and nothing is sticking to the seed. Then measure the mass of the bird seed in a souffle cup. The second steps determined were by size because if the larger material, such as bird seed got wet, then the result of recovered mass would be harder to determine

The purpose of this experiment is to familiarize oneself with the general procedures determining a partition coefficient at the microscale level and learn in weighing milligram quantities of materials on an electronic balance, the use of automatic pipets, the use of transfer pipet, and the use of a vortex mixer. Also, to familiarize oneself with extraction

This hypothesis relates to the experiment by saying how when different liquids were used, there were many different reactions. Proving the hypothesis is supported. The experiment could be done differently by using other powders, liquids, etc. This could cause many changes. One thing is the expansion of options. It would have many substances to compare to the unknown. Thus creating a lot more options for the unknown powder to be. It could also increase the probability of error, from having so many different resources. Sources of error could include adding too much powder and not enough liquid. Doing this could cause the balance to be off. For example, not adding enough liquid could cause the powder to not react. When in reality, the substance usually fizzes or changed color. Doing this experiment made learning about different reactions to different substances

Chromatography is a separation technique in which the mixture to be separated is dissolved in a solvent and the resulting solution, often called the mobile phase, is then passed through or over another material, the stationary phase. The separation of the original mixture depends on how strongly each component is attracted to the stationary phase. Substances that are attracted strongly to the stationary phase will be retarded and not move alone with the mobile phase. Weakly attracted substances will move more rapidly with the mobile phase.

Quantitative analysis is the determination of an amount present in a variety of settings. On the other hand, qualitative analysis is the determination of non-numerical information about a reaction, such as observing that a reaction results in a color change. There are chemical changes that separate cations and physical separations, such as decanting, where liquid is poured from a solid-liquid mixture, leaving the solid behind. Centrifuging is another separation technique, where a solid is separated from a liquid by whirling the mixture at high speed. A mixture of metal ions in a solution can be separated by a reaction of precipitation and in this experiment, the metal cations of aluminum, nickel, and iron ions will be separated from a solution

1. Obtain a sample of the mixture. The mixture you will separate contains three components: NaCl, NH4Cl, and SiO2. Their separation will be accomplished by heating the mixture to sub-lime the NH4Cl, extracting the NaCl with water, and drying the remaining SiO2.