Understanding Chemical Reactions and Properties of Elements

Posted by on Aug 27, 2024 in Chemistry | 0 comments

Nascent Hydrogen

Nascent Hydrogen is a more energetic and powerful reductant than molecular hydrogen. Here’s why:

a. Reduction of Potassium Permanganate: Nascent Hydrogen reduces acidified potassium permanganate, decolorizing it, while ordinary hydrogen cannot.

Reaction: 2H2SO4 + 3KMnO4 + 10[H] → K2SO4 + 2MnSO4 + 8H2O

AND H2SO4 + KMnO4 + H2 → No Reaction

b. Reduction of Potassium Dichromate: Nascent hydrogen reduces acidified Potassium Dichromate solution, changing its color from orange to green,

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Titration & Electrochemistry Experiments: A Comprehensive Guide

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Titration and Electrochemistry Experiments

Acid-Base Titrations

3. Titration of Strong Acid with NaOH

This experiment involves titrating a strong acid (hydrochloric acid) with a strong base (sodium hydroxide).

  1. Measure 10ml of an unknown HCl solution into a titrating flask.
  2. Add 3 drops of methyl orange indicator.
  3. Fill a buret with 0.1 N NaOH.
  4. Titrate the unknown HCl until the color changes to radish-yellow.
  5. Repeat the experiment twice.
  6. Use the mean value for calculations.

4. Titration of Acetic Acid with NaOH

This

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Chemistry Basics: Key Concepts and Formulas

Posted by on Aug 27, 2024 in Chemistry | 0 comments

Chemistry Basics

Fundamental Concepts

Chemical Reactions

Synthesis: A + B -> AB
Decomposition: AB -> A + B
Single Displacement: A + BC -> AC + B
Double Displacement: AB + CD -> AD + CB

Avogadro’s Number and Molecular Mass

Avogadro’s Number: 6.022 x 1023
Molecular Mass: The number under the element symbol (amu)
Formula Mass: Sum of atomic masses of all elements in a compound
Molar Mass: Mass of one mole of a substance (grams)

Calculating Moles and Mass

Moles in grams: Divide grams by molar mass (amu)

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Chemistry Concepts: Chapters 4, 5, and 7 Overview

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Chapter 4: Reactions in Aqueous Solutions

Key Concepts:

  • Electrolytes:
    • Argon (Ar) is not an electrolyte.
    • A strong electrolyte ionizes completely in solution.
    • A weak electrolyte exists predominantly as molecules in solution.
  • Reactions:
    • Aqueous potassium chloride will react with lead nitrate in an exchange (metathesis) reaction.
    • Zinc sulfide (ZnS) is insoluble in water.
    • A neutralization reaction between an acid and a metal hydroxide produces water and a salt.
    • Oxidation cannot occur without reduction.
  • Acids and
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Stoichiometry and Thermochemistry MCQ Practice with Answers

Posted by on Aug 26, 2024 in Chemistry | 0 comments

Topic 1: Stoichiometry

Questions and Answers

1. What amount of oxygen, O2, (in moles) contains 1.8×1022 molecules?

B. 0.030

2. Which compound has the empirical formula with the greatest mass?

B. C4H10

3. __C2H2(g) + __O2(g) → __ CO2(g) + __ H2O(g)

When the equation above is balanced, what is the coefficient for oxygen?

D. 5

4. 3.0 dm3 of sulfur dioxide is reacted with 2.0 dm3 of oxygen according to the equation below.

2SO2(g) + O2(g) → 2SO3(g)

What volume of sulfur trioxide (in dm3) is formed? (Assume

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Organic Chemistry Key Concepts & Reactions

Posted by on Aug 26, 2024 in Chemistry | 0 comments

Organic Chemistry: Key Concepts & Reactions

Benzene & Its Derivatives

Structure & Stability of Benzene

Benzene is a cyclic, planar molecule with six carbon atoms. Each carbon atom is bonded to two other carbon atoms and one hydrogen atom via single covalent sigma bonds, resulting in a trigonal planar geometry with bond angles of 120 degrees. This leaves one unused electron on each carbon atom in a p-orbital perpendicular to the plane of the ring. These p-orbitals overlap with neighboring

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