Hydrochloric Acid Lab

H. How would you prepare 10 mL of a 0.25M HCl solution if 1M HCl was available? How much

The results showed the molarity of the NaOH solution. This experiment was completed twice and a new average molarity

HYDROCHLORIC ACID IS A CORROSIVE SUBSTANCE WHICH CAN CAUSE DAMAGE TO SKIN AND OTHER SUBSTANCES. IT HAS STRONG VAPORS. WEAR GOGGLES AND AN APRON. YOUR TEACHER WILL SHOW YOU HOW TO POUR THE ACID SAFELY. IF YOU SPILL ACID ON YOURSELF, WASH IT OFF WITH LOTS OF RUNNING WATER. A FEW DROPS SPILLED ON THE LAB BENCH CAN BE CLEANED UP WITH A PAPER TOWEL. A LARGE SPILL SHOULD BE NEUTRALIZED WITH BAKING SODA, AND THE RESULTING NEUTRAL SUBSTANCE CAN THEN BE WASHED INTO THE SINK WITH A

3.6.3. 2, 4 – D (2, 4–Dichloro phenoxy acetic acid) stock solution (1mg/ml): 10.0mg of 2.4-D being weighed and dissolved completely in 1N NaOH to a final total volume

Bases are a substance with a pH higher than 7, and have a high concentration of hydroxyl ions. Bases can react with acids in order to neutralise them in order to form salt and water. Bases are normally metal oxides or metal hydroxides. Sodium hydroxide for example is a base.

Hydrochloric acid (HCl) has risks as it is a corrosive compound. Corrosive compounds, including HCl, can cause injuries such as burning and eating away skin and eyes. To prevent such injuries, do not come into physical contact with HCl. Wear safety glasses, safety gloves and lab clothing.

An acid is a chemical substance that typically has a corrosive or sour-taste and turns litmus paper red. It has a pH of below 7 and can generally dissolve some metals or even neutralize alkalis. A base on the other hand, is the opposite. They have a bitter taste and are very aqueous. Their pH rating is above 7 and they turn litmus paper blue. In science, pH is the negative log of the activity of the hydrogen ion in an aqueous solution. Basically, we find the pH of a substance by using a testing strip or litmus paper to see the amount of H+ atoms in it. Litmus paper, a common indicator, is used to easily test the pH level of a substance. We can see how acidic or basic a substance is by comparing it to others on a pH scale. A pH scale ranges from 0-14, the most acidic being 0 and most basic being 14. Lemon juice, for example, has a pH of 2 meaning its very acidic. However, average dish soap has a pH of 7-8. The only thing left is a pH level of exactly 7. A pH of 7 is perfectly neutral, not acidic or

Caution – Hydrochloric acid is corrosive to eyes, skin and clothes. Wearing a lab apron, rubber gloves, goggles, and a face shield is essential. Rinse any spills on skin or clothing with plenty of cold water. Clean up spills immediately – ask your instructor for help.

A. Figure 1: Standard curve of the phosphate concentrations and the absorbance values. This curve shows the amount of light that is absorbed by the reaction of water with 1 mM phosphate in six different test tubes, containing different volumes of water and phosphate in each tube. Tube 1 contained 1 mL of water with 0 mL of phosphate, tube 2 had 0.8 mL of water with 0.2 mL of phosphate, tube 3 consisted of 0.6 mL of water with 0.4 mL of phosphate, tube 4 had 0.4 mL of water with 0.6 mL of phosphate, tube 5 had 0.2 mL of water with 0.8 mL of phosphate, and tube 6 had 1 mL of phosphate with no water present. After all of the solution was added to the test tubes, 2.5 mL of stopping reagent was added to each test tube in order to denature the enzyme and stop the reaction. After 10 minutes, the absorbance was measured at 620 nm; which are the values used to create this curve based on phosphate concentration.

This showed that there was a limiting reactant in the Alka-Seltzer tablet that forced the production of product to end. When the volume of vinegar reached 10 mL, the average mass of NaHCO3 plateaued equating to an average of 45% by mass of NaHCO3. Due to the high amount of trials, the accuracy in the determination of percent by mass of NaHCO3 increased. However, the standard deviation showed that the precision was low. This brings The percent by mass of NaHCO3 in each tablet in this experiment increased as the amount of vinegar used in solution increased.

In order to find the molar volume of a gas at standard temperature and pressure (STP), one could create a reaction between a magnesium (Mg) ribbon and excess hydrochloric acid (HCl). By having HCl put into a eudiometer tube, then adding DI water nearly to the brim, one can then add Mg, by means of a copper wire cage attached to the tube stopper. The tube thereafter, is inverted and directly put into a bath of water. Due to HCl’s greater density than water, HCl will move down to the now-bottom of the eudiometer tube and react with the Mg ribbon. The reaction yields liquid magnesium chloride (MgCl2)and hydrogen gas (H2); the gas particles of H2 will then move to the top of the tube, where it is trapped.

At second trial, initial volume was 38.38mL and we used 1.24mL for the titration and the final volume of NaOH was 39.62mL and the molarity of NaOH was 0.40M NaOH. At last (third) trial, the initial volume of NaOH was 39.62mL and we used 1.09mL for the titration and the final volume of NaOH was 40.71mL. According to the volume of NaOH increased, the molarity of NaOH decreased. Based on the experiment, the relationship between volume and molarity of NaOH is inverse.

My hypothesis was that the shells will slowly erode the shells. My hypothesis is correct because the cup with the biggest change in acid also had the biggest weight change. I know my hypothesis is correct because the shells all changed at least a little in weight. One thing I did not state that should have been stated was that the more amount of acid the more it affects the erosion of the shell. I think that i can prove my hypothesis true if I continued this research until it finally completely erodes. Something is true from what I learned and

The colour change because of addition of base that remove hydrogen and produce more phenolphthalein ions. (Reference.com, 2016). The average volume of NaOH is 77.1 mL when the colour of the solution had changed into faint pink (Revised Spring NF, p.4, 2004). In 2.1.4, Pearson square method was used for dilution. This method used arithmetic ratio technique known as allegation. Allegation is “a process or rule for the solution of problems concerning the compounding or mixing of ingredients differing in price or quality” (small & us, 2016). Pearson square method is a simple method that used when combine two elements together with simple ratios and produce higher value (Wagner and Stanton, 2012). Formula M1V1=M2V2 also can be used in this problem if B=0 which is B is molarity of dilute solution but if B≠0, Pearson square method must be used. Lastly, the volume HCL needed is 1.9 mL and molarity of HCL gain is 0.01

The purpose of this lab was to use process titration to find concentration of an aqueous solution of Hcl(aq) , using KOH(aq) as the titrant.