Double Displacement Reaction Lab Report

To determine which ions are present in the two unknown solutions. This will be accomplished by mixing three known solutions with three testing solutions. You will use this information to determine which ions are present in the unknown solutions.

Heavy precipitate emerged immediately and solution turned white in color; solution then became opaque and turned light, bright blue in color.

The objective of the experiment was to observe different reactions with different chemicals. The experiments emphasized on the chemical changes occurring in acids and bases as well as color changes and bubble formations. The experiments allowed for a better understanding of the undergoing chemical changes in mixtures. Some mixtures instantly changed colors while others were transparent or foggy. Some mixtures produced thick color that created solids called precipitates. Mixtures KI + Pb(NO3)2 and NaOH + AgNO3 both produce noticeable precipitates after a while. It was interesting to see the different acidic and base reactions like the fuchsia color formation in NaOH + phenolphthalein.

3. When two solutions combine and a solid substance is formed, this solid is called a precipitate. In your experiments, if the clear reactant solutions you combined together formed a cloudy product, then a precipitate (solid substance) was formed. Describe the precipitates (according to color and clarity) and the substances that formed them. (18

Although it did take some time, when red litmus paper was placed in the solution, it changed blue in colour, therefore highlighting that hydroxide ions are present in the solution. Station four can clearly be identified as a combination (redox) reaction, as a new product is synthesised by the combination of two reactants. The reactants, calcium and water combine together to form hydrogen gas and hydroxide ions.

Many signs show that a chemical reaction has occurred. Some ways we know there is a chemical reaction are the formation of gas, formation of precipitate, change in temperature, and,or change in color. In part one of the experiment, we know there was a chemical change because of the formation of the white precipitate. We poured the ammonia and water in the flask with alum and water, forming a white, cloudy substance in between the two liquids. The white, cloudy substance between the two is liquids is also known as aluminum hydroxide. The second part of the experiment was very similar to the first, but in the second part we mixed epon salt, water, and ammonia. The precipitate formed from mixing the epson salt, water, and ammonia was called magnesium hydroxide.

The methods used for part one was (I) to pick between part A or part B. (II) weigh out the part that you picked. And lastly (III) let the chemicals precipitate when adding distilled water. The methods that were used during the second part of the lab was to calculate how much of the compounds that you need than to add 5ml distilled water to both and combine together. What was found in this lab was which chemical compound from the product of the equation is the limiting reactant.

Every reaction that occurred during this lab was a double replacement reaction, or a chemical reaction in which two aqueous compounds react with each other and result in two different compounds where one is either a solid precipitate, a liquid (water), or a gas. A precipitate in this case is a solid that exits the aqueous solution during the chemical reaction because it is too heavy to stay in the solution. Clear signs of a chemical reaction occurring is the formation of a precipitate, especially in a double replacement reaction, as well as the release of gas bubbles and the product of an acid. During a double replacement, the elements “switch partners” as seen with the base equation for all double replacement reactions, AB+CD→AC+BD. For a lab such as this, a hand lens could be used to confirm the presence of gas bubbles or a precipitate that would not have easily been seen without the device.

A double displacement, or double replacement or double exchange-reactions (also known by several other names), are ones in which the cations of the reactants are reversed in the products. A generic formula for this is AB+CD →AD+CB. (Zumdahl). A specific type of double-displacement reactions is also a precipitation reaction. A precipitation reaction occurs when there is the “formation of a solid when two solutions are mixed” (DeCoste and

Reaction B: Cu(NO3)2(aq)+ 2NaOH(aq) → Cu(OH)2(s)+ 2NaNO3(aq) Reaction C: Cu(OH)2(s) → CuO(s)+ H2O(l) Reaction D: CuO(s)+ H2SO4(aq) → CuSO4(aq)+ H2O(l) Reaction E: CuSO4(aq)+ Zn(s) →ZnSO4(aq)+ Cu(s) ZnSO4(aq)+ H2SO4(aq) →ZnSO4(aq)+

Predicting Precipitations Lab Report: explanation data of lab along hypothesis, and identifying possible errors of lab for further investigations. The reactions from 1A through 1D all have a precipitation formed because physical changes appeared. AgNo3 is a clear solution; when it is mixed with a yellow FeCl3, a precipitate is formed in a different color than the original colors. After a while, the precipitate became slightly solid. For 1B and 1C, the solid was formed in similar ways, it might be because both reactants contains a similar element.

Also when mixed with Magnesium Sulfate both Ammonium Hydroxide and solution A do not react, therefore mixing Magnesium Sulfate with those compounds doesn’t cause a double displacement reaction. Of course testing solution A and Ammonium Hydroxide with more chemicals side by side would give us more confidence in our answer, but Kate and I are highly confident in our answer

AB → A+ B In contrast to synthesis, combustion, and decomposition reactions, many chemical reactions are replacement (also called displacement) reactions and involve the replacement of an element in a compound. There are two types of replacement reactions; single replacement reaction, in which the atoms of one element replace the atoms of another element in a compound, A + BX -> AX + B; and double replacement reactions, in which an exchange of ions between two compounds is involved, AX + BY → AY +

The reaction between sodium sulfate (Na2SO4) and barium chloride (BaCl2) created a white precipitate. This reaction possibly

The main purpose of this experiment was to show that single displacement reactions between metals according to their reactivity, with more reactive elements having the power to displace less reactive elements and take their place in a chemical compound (Beran, 2014). This was supported by the results of the experiment, where solid metals were combined with aqueous solutions that contained another element, and reactions only took place when the solid metal was more reactive than the other element in the compound. Only three attempted trials resulted in a failure to produce a reaction, namely the combinations of copper with hydrochloric acid, and copper with nickel sulfate. The outcomes of these trials are justifiably reasonable because copper is ranked lower in the