How can i explain the key features of the periodic table relate to the conclusions after a titration experiment
The experiment was the preperation of a standard solution of sodium carbonate and titration for the equation between hydrchloric acid and sodium carbonate
Objective : To prepare a standard solution of sodium carbonate and use it to standardize a given solution of dilute hydrochloric
acid.
Introduction : Anhydrous sodium carbonate is a suitable chemical for preparing a standard solution (as a primary standard). The
molarity of the given hydrochloric acid can be found by titrating it against the standard sodium carbonate solution
prepared.
The equation for the complete neutralization of sodium carbonate with dilute hydrochloric acid is
Na2CO3(aq) + 2HCl(aq) → 2NaCl(aq) + CO2(g) + H2O(l)
The end-point is marked by using methyl orange as indicator.
Chemicals : solid sodium carbonate, 0.1 M hydrochloric acid
Apparatus :
Procedure : 1. Weight out about 1.3 g of anhydrous sodium carbonate accurately using the method of “weighing by
difference”.
2. Transfer the weighed carbonate to a beaker and add about 100 cm3 of distilled water to dissolve it completely.
3. After dissolving, transfer the solution to a 250.00 cm3 volumetric flask. Rinse the beaker thoroughly and
transfer all the washes into the volumetric flask. Remember not to overshoot the graduation mark of the flask.
4. Make up the solution to the mark on the neck by adding water.
5. Pipette 25.00 cm3 of sodium carbonate solution to a clean conical flask.
6. Add 2 drops of methyl orange indicator to the carbonate solution.
7. Titrate the carbonate solution with the given dilute hydrochloric acid until the colour of solution just changes
from yellow to orange.
I can tell you how to compute the molarity of the HCl but I have no clue how that relates to any conclusions about the periodic table.
moles Na2CO3 = mass Na2CO3/molar mass Na2CO3.
Moles HCl = twice moles Na2CO3
M HCl = moles HCl/L HCl in the titration.
The mass of the Na2CO3 solution used in the titration is (25 mL/250 mL = 1/10) the mass of what you weighed out into the volumetric flask.
The key features of the periodic table can relate to the conclusions drawn after a titration experiment in several ways:
1. Atomic Mass: The atomic mass of an element can be used to calculate the molar mass of a compound, allowing for the determination of the concentration of the standard solution. In this case, the molarity of the hydrochloric acid can be found by titrating it against the standard sodium carbonate solution. The atomic mass of sodium (Na) and carbon (C) can be obtained from the periodic table to calculate the molar mass of sodium carbonate (Na2CO3).
2. Valence Electrons: The valence electrons determine the chemical properties of an element. In the titration process, the reaction between sodium carbonate and hydrochloric acid involves the transfer of electrons. By knowing the number of valence electrons of sodium and chlorine from their respective positions in the periodic table, one can understand the electron transfer and bond formation during the reaction.
3. Periods and Groups: The periodic table is organized into periods (horizontal rows) and groups (vertical columns) based on similar properties of elements. This organization helps in predicting trends and patterns in various properties, such as reactivity and acidity/basicity. In this case, sodium carbonate belongs to Group 1 (alkali metals) and hydrochloric acid belongs to Group 17 (halogens). The periodic table can be used to infer that the reaction between an alkali metal carbonate and a halogen acid will produce a salt, carbon dioxide gas, and water.
4. Indicators: Indicators are chemicals that change color at specific pH values. In this titration experiment, methyl orange is used as an indicator. By referring to the periodic table, you can determine which compounds are suitable indicators by considering their chemical structure and behavior. In the case of methyl orange, it changes color from yellow to orange in the presence of a specific pH range, indicating the endpoint of the reaction.
To summarize, the periodic table provides information on atomic mass, valence electrons, chemical properties, and indicators. By understanding these key features, one can analyze and interpret the results of a titration experiment, such as the molarity of the hydrochloric acid and the endpoint of the reaction.