Organic chemistry is the chemistry of carbon and its compounds. Carbon is one element of the Mendeleev table among many others, so why is there a complete section of chemistry related to this particular element? Carbon has a valence of 4 and can thus bind with up to 4 other elements of the periodic table. […]
Posts in the 1st Year category:
Chapter 2c: Neutralization and titration
Neutralization A neutralization reaction is the reaction occurring between an acid and a base forming a salt and water. Technically, the neutralisation is not a one step reaction in the sense that all the actions are not done simultaneously but step by step. The fist step is the dissociation of the acid and base from […]
Chapter 2b: Strength of acids and bases
The general definition of an acid is thus a compound releasing protons. However, all the acids don’t have the same strength or acidity. We can define two types of acids and bases: Strong acids and bases, and weak acids and bases. For more simplicity, we will focus on acids in this lesson but the principle is identical for […]
Chapter 2a: acid-base reactions
In this module we will review one of the main types of reaction of chemistry. Reactions can indeed be classified in 3 major categories: Acid-base reactions Redox (reduction and oxidation) reactions Solubility reactions (dissolution and precipitation) The two last reaction types are seen in other sections of our lessons. We will here focus on acid-base […]
Chapter 1: history of chemistry and chemical reactions
It is often useful to take a look on the history of something to understand it. That is how we will begin our lessons about chemistry. As far as we can go, chemistry started with the discovery of fire, which is basically the combustion of a reactant to obtain heat from it. Later, different metals […]
Chapter 5 : exercices and exam questions (probability)
Problem 1: A marketing survey indicates that 60% of the population owns an automobile, 30% owns a house, and 20% owns both an automobile and house. Calculate the probability that a person chosen at random owns an automobile or a house, but not both. (A) 0.4 (B) 0.5 (C) 0.6 (D) 07 (E) 09 Problem […]
Chapter2: torque and angular momentum in circular motion
Definitions: the torque and angular momentum are defined as vector products of position, force and momentum. Suppose a forceacts on a particle whose position with respect to the origin 0 is the displacement vector . Then the torque “about the point 0 and acting on the particle,” is defined as: Now suppose the particle has […]
Chapter 1: uniform circular motion
When an object has a circular motion even though its speed is constant, it is nonetheless accelerating because according to newton’s 1st law: an object continues in its state of rest or uniform motion unless acted on by an external force. So if the object was to be free in space then of course it will […]
Chapter 8 : TRANSCRIPTION
. The central dogma of molecular biology The central dogma is the classic sequence of events : DNA produces RNA by transcription and RNA produces proteins ( structural proteins […]
Chapter 7 : Photosynthesis
Photosynthesis Photosynthesis is the process that converts solar energy to chemical energy. Directly or indirectly, photosynthesis nourishes almost the entire living worlds -Autotrophs sustain themselves without eating anything derived from other organisms -Autotrophs are the producers of the biosphere, producing […]