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Maslow's Theory of Basic Human Needs01:28

Maslow's Theory of Basic Human Needs

Maslow's hierarchy is described with the help of a pyramidal shape. The most fundamental needs, physiological needs, are at the bottom of the pyramid.
Physiological needs such as hunger, thirst, sex, physical comfort, and survival are at the bottom of the pyramid. These are the components that are necessary to sustain life. Once the first level of needs has been met, the second level arises.
Safety needs include stability and predictability. Protection and freedom from danger are all a part of...
Maslow's Need Hierarchy Theory01:27

Maslow's Need Hierarchy Theory

Abraham Maslow's theory of motivation, introduced in 1943, is widely known as the "Hierarchy of Needs." This theory posits that human needs are arranged in a hierarchical structure, starting with basic survival needs and progressing toward more complex psychological and self-fulfillment desires. The hierarchy is typically a pyramid, and the lower needs must be satisfied to reach the next level.
At the pyramid's base are physiological needs, including food, water, and shelter — essentials for...
Trophic Levels01:35

Trophic Levels

All organisms in an ecosystem occupy a trophic level in the food chain. The lowest level consists of primary producers, which synthesize their food from either solar or chemical energy. Each subsequent level obtains energy from the levels below. Detritivores can occupy any of the levels above primary producers.
Weak Base Solutions03:21

Weak Base Solutions

Some compounds produce hydroxide ions when dissolved by chemically reacting with water molecules. In all cases, these compounds react only partially and so are classified as weak bases. These types of compounds are also abundant in nature and important commodities in various technologies. For example, global production of the weak base ammonia is typically well over 100 metric tons annually, being widely used as an agricultural fertilizer, a raw material for chemical synthesis of other...
Base Quantities and Derived Quantities01:14

Base Quantities and Derived Quantities

In any system of units, the units for some physical quantities must be specified through a measurement process. These measurements are the base quantities of the system, and their units are the base units of the system. The algebraic combinations of the base values can then be used to express all other physical quantities. Each of these physical quantities is then referred to as a derived quantity, with each unit being referred to as a derived unit.
The International Organization for...
Ladder Diagrams: Acid–Base Equilibria01:32

Ladder Diagrams: Acid–Base Equilibria

Understanding the chemistry between the reagents is necessary for performing any experiment. To this end, scientists have designed a tool called a ladder diagram, which is a graphical representation that helps illustrate the chemistry of a system.
A ladder diagram for acid-base equilibria consists of a vertical axis that represents pH and horizontal bars (steps on the ladder) that help position all the pKa values in the system. At equilibrium, the pH value of the system corresponds to one of...