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Showing posts with label General Science. Show all posts
Showing posts with label General Science. Show all posts

Compound and mixture; Examples and differences

March 08, 2021

Compound
A compound is formed from the combination of two or more element which are chemically combined together. Examples are:

• marble chips/ Limestone/ Chalk (Caco3),
• sodium chloride (Nacl),
• caustic soda or Sodium hydroxide (Na OH),
• Lime water or calcium hydroxide (Ca(OH)2
• Lime (Cao)
• Epsom salt/water (MgSO4. 7H2O)
• Urea (CH4N2O)
• Clay (Al2O3 2SiO2 2H2O

Chemistry: What is Hydrogen? Its Uses, physical properties, chemical properties and methods of preparation

March 06, 2021

Hydrogen is found in group one of the periodic table. Though, it is non-metal, it is usually placed in group one because it has one valence electron.

Physics: Equations of Motion, derivation, Questions and solutions

February 27, 2021

In the last article, The definition and types of Motion were discussed. Now this is an article to better understand Equations of motion with several questions solved.

Physics: Motion, types, Terms and terminologies

February 27, 2021

Motion

This is the change in the position of a body in respect to time. It also involves how things move and what makes them to move.

States, properties and uses of Matter

February 27, 2021

1) Define matter
2) Know States of Matter
3) Differentiate between solid, Liquid and gas
4) properties of Matter
5) Name several uses of matter

South African Countries and flag map

May 15, 2020
There are 54 countries on the African Continent. Today,  we will go  through countries in the Southern part of Africa.

Watch the video on Southern African countries;

Difference between Mass and Weight with related questions

May 02, 2020

Mass

A mass of a body is the quantity of matter contained in that body. It is a scalar quantity I.e. it has magnitude but no direction. The unit of mass is kilogramme (kg).

Fundamental, Derived quantity, units and dimensions

January 01, 2020

Fundamental Quantity
In Physics and general science, fundamental quantities are base/physical quantities independent of all other quantities. They are measured in base or fundamental units. Length (L), Mass (M), Temperature (K), Mole (Amount of substance) (mol), current (Ampere), Luminous intensity (Candela).

Derived Quantity
In physics and general science, derived quantities are quantities that are dependent on fundamental quantities and are measured by the simple and easy combination of fundamental quantities. Some  Examples are: Electromotive force (EMF), density, volume, momentum, Area and so on.

Watch Summary video for fundamental and derived quantity.

What is Emulsion? Types, Examples and Quiz

December 30, 2019

In the previous article on Emulsifiers, the concept of emulsion was highlighted on.

What is Emulsion?
Emulsion is definitely a common term in the chemistry world. Emulsion is the mixing or colliding of one liquid with another liquid the are normally insoluble in each other. It is a type of Colloid action. Although, the mixture of the two immiscible (insoluble) liquids will separate again after a period of time, unless an Emulsifier is added to it.

Types of Emulsion
1) Water-in-Oil Emulsion: Here, the water is suspended in an oil mix. This emulsifier suitable for stabilizing this type of emulsion is more soluble in water and less soluble in oil. An Example is Ice cream.

2) Oil-in-Water Emulsion: Here, the oil is suspended in water mix. This emulsifier suitable for stabilizing this type of emulsion is more soluble in oil and less soluble in water.An Example is Lotions.

POP Quiz:
Task: Spot and answer the 3 test question in the Video below.
Leave the answers in the comment section.

Some food emulsifiers are egg yolk, Monoglyceride & Diglyceride, Mucilage (in mustard) and many some others.

Emulsifiers; definition, Compositon, Hydrophilic and lipophilic Simple Explanation

December 30, 2019

General Concept of Emulsifiers (All you need to know)

Emulsifier

This is a chemical/substance/compound that assists in stabilizing an Emulsion. Emulsion is the suspension or dispersion of a liquid in another liquid that are not normally soluble (Immiscible) and forms an heterogeneous mixture.

Why doesn't Oil and water Mix?
Oil has molecules that are as Non-polar and therefore can not mix or be soluble in Water which has polar molecules.

Figure one, Oil floating on water as a result of difference in a variable density.

 Oil/Water don't mix

Only Polar molecules can dissolve and attract other polar molecules. This is as a result of the said molecules having charges on both ends. That is, one end of the each molecule has a positive charge and the other end has a Negative charge.

Oil molecules are non polar molecules and therefore can not mix with polar molecules. This is because Non-polar attracts non polar.

Hydrophilic and lipophilic
For Figure two below,  Working principle of Emulsifier.

 Hydrophilic and lipophilic

The Emulsifier generally composes of a Water loving Hydrophilic head region and the Oil-Loving Lipophilic tail. Emulsifiers has several uses, functions and application with its distinct feature in helping to stabilize texture and increase shelf life of Food and Cosmetics.