Analía Bellizzi – Chemistry Classes

Ronald Reagan Senior High School

Rate of Reactions Lab #2 Alka-Seltzer and water.

  1. The purpose of this lab is: (You complete it)
    …………………………………………………………………………………………………………………..

Procedures

  1. Watch the videos and write down the procedures. 

Lab setup (Draw it yourself, do NOT use a picture or copy and paste. Label your lab setup)

The video below corresponds to the reaction with cold water

The video below corresponds to the reaction of Alka-Seltzer with hot water

Data tables (use graph paper)

  • Build up the data table based on the video information

Graph

    1. Graph showing the time in the “X” and the mass loss as “Y” (use graph paper).
    2. Use ONLY ONE GRAPH for both experiments. Mark the values for hot acid using red pen/pencil. Mark values of cold acid using a blue pen/ pencil
    3. Do not connect the dots, draw the line (curve) of best fit. 

 

Materials

  1. Beaker with water (100 cm3)
  2. Timer or camera with timer.
  3. Alka-Seltzer tablet
  4. cotton ball
  5. balance (as precise as possible)

Analysis questions

1)      How would the graph look like if you use water at 0 ºC? (sketch in a small piece of paper showing your hot and cold water in red and blue and the prediction in black)

2)      How would the graph look like if you use 2 tablets of Alka-Seltzer instead of 1?              (sketch both graphs in one)

3)      What would you expect to see if you crush the tablets into powder? Why?

4)      What is the gas that was released? How can you prove it in the lab?

5)   Which is the limiting reactant in the reaction produced in the conical flask? How can you tell?

Items to show in the LAB REPORT

  • 1- TITLE
  • 2- LAST AND FIRST NAME OF MEMBERS
  • DATE
  • PURPOSE OF THE LAB (How the temperature affects the rate of a reaction)
  • MATERIALS
  • DATA TABLES: Data tables must be built  WITH RULERS, using units ONLY ON THE HEADER. (Do not repeat the unit in every row)
  • Graphs & Charts MUST BE AS FOLLOWS
    • In graph paper.
    • with LABELLED AXES AND UNITS
    • TIME MUST BE ON X AXIS
    • VOLUME MUST BE ON Y AXIS
    • using ruler
    • scale must be uniform (the distance between the same quantities must be represented by the same distance.
    • line graphs ONLY will be accepted
    • DO NOT CONNECT THE DOTS one by one, draw a smooth line touching as many dots as possible
  • Least squares fit
  1.