Posts

Showing posts with the label Chemistry

Recent Post

What is thermometry?

Thermometry The branch of heat relating to the measurement of the temperature of a body is called thermometry. The thermometer is an instrument used to measure the temperature of a body. The essential requisites of a thermometer are given as under:  1) Construction, 2) Calibration, and 3) Sensitiveness. For the construction of a thermometer, the proper choice of a substance, whose physical property varies uniformly with rising in temperature, is essential. 1) Construction The physical property of a substance plays an important role in the construction of a thermometer. In a mercury thermometer, the principle of expansion of mercury with rising temperature is used. The platinum resistance thermometer is based on the principle of the change in resistance with a change in temperature. The gas thermometer is based on the principle of change in volume or pressure with a change in temperature. 2) Calibration  When a thermometer is constructed, it should be properly calibrated. The standa

Changing of states of matter- Solid, Liquid and Gases

The kinetic theory model can be used to explain how a substance changes from one state to another. If a solid is heated the particles vibrate faster as they gain energy. This makes them ‘push’ their neighboring particles further away from themselves. This causes an increase in the volume of the solid, and the solid expands. The expansion has taken place. Eventually, the heat energy causes the forces of attraction to weaken. The regular pattern of the structure breaks down. The particles can now move around each other. The solid has melted. The temperature at which this takes place is called the melting point of the substance. The temperature of a pure melting solid will not rise until it has all melted. When the substance has become a liquid there are still very significant forces of attraction between the particles, which is why it is a liquid and not a gas. Solids that have high melting points have stronger forces of attraction between their particles than those which have low meltin

Explaining the three states of matter

Image
In a solid, the particles attract one another. There are attractive forces between the particles which hold them close together. The particles have little freedom of movement and can only vibrate about a fixed position. They are arranged in a regular manner, which explains why many solids form crystals.  It is possible to model such crystals by using spheres to represent the particles. If the spheres are built up in a regular way then the shape compares very closely with that of a part of a chrome alum crystal. Studies using X-ray crystallography have confirmed how the particles are arranged in crystal structures. When crystals of a pure substance from under a given set of conditions, the particles present are always packed in the same way. However, the particles may be packed in different ways in crystals of different substances. For example, common salt (sodium chloride) has its particles arranged to give cubic crystals as shown in Figure. In a liquid, the particles are still close t

The kinetic theory of matter

The kinetic theory helps to explain the way in which matter behaves. The evidence is consistent with the idea that all matter is made up of tiny particles. This theory explains the physical properties of matter in terms of the movement of its constituent particles. The main points of the theory are: All matter is made up of tiny, moving particles, invisible to the naked eye. Different substances have different types of particles (atoms, molecules, or ions) that have different sizes. The particles move all the time. The higher the temperature, the faster they move on average. Heavier particles move more slowly than lighter ones at a given temperature. The kinetic theory can be used as a scientific model to explain how the arrangement of particles relates to the properties of the three states of matter. You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple dis

What is activation energy?

The least amount of energy required for active atoms or molecules to a state in which they can undergo a chemical reaction is known as activation energy.  You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is catalyst poison?

The substances which destroy the catalytic activity of a catalyst are known as catalyst poisons.  You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is catalyst?

The substances that make a reaction take place faster but are not used up in the reaction are called catalysts.  You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is rate of reaction?

The rate of decrease of concentration of a reactant or the rate of increasing concentration of the product is known as the rate of reaction. You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is green chemistry?

Green chemistry is the utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and application of chemical products. You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is essential oil?

The oil which is extracted from roots, leaves, flowers, and seeds is known as an essential oil. For example - Amla, Olive etc. You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is perfumery?

Perfumeries include different types of cosmetics and perfumed personal care products. You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is coagulation?

Coagulation is a process of bringing the suspended fine particles together to form a bulk material. You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is molt vinegar?

Conversion of barley's starch or sugar into acetic acid by the process of malting is known as malt vinegar. This vinegar is widely used in making pickles. You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is suspension?

Suspension is a kind of non-homogenous mixture. In a suspension, the solute particles can be observed by naked eye or microscope. If kept standing, the solute particles settle at the bottom. You may also read Types of Computer Main components of computer systems Hardware and Software Liquids which are miscible Liquids which are immiscible Separating liquid mixtures Simple distillation 

What is preservatives?

Natural or chemical substances which are used in a small amount to protect food from the contamination of micro-organisms. Preservatives increase the shelf-life and taste of food. You may like Do I need car insurance? What is car insurance? How could I get cheaper car insurance? What is auto insurance? Why Adulterant food is the barrier to sound health? What are the producers? What are food preservatives? What is food chain? What is tertiary consumer?

What is an ion?

Compounds composed of metals and nonmetals contain charged species. The charged species are known as ions. An ion is a charged particle and can be negatively or positively charged. A negatively charged ion is called an ‘anion’ and the positively charged ion, a ‘cation’. Take, for example, sodium chloride (NaCl). Its constituent particles are positively charged sodium ions (Na + ) and negatively charged chloride ions (Cl - ). Ions may consist of a single charged atom or a group of atoms that have a net charge on them. A group of atoms carrying a charge is known as a polyatomic ion. You may like Do I need car insurance? What is car insurance? How could I get cheaper car insurance? What is auto insurance? Why Adulterant food is the barrier to sound health? What are the producers? What are food preservatives? What is food chain? What is tertiary consumer?

Molecules of elements

The molecules of an element are constituted by the same type of atoms. Molecules of many elements, such as argon (Ar), helium (He), etc. are made up of only one atom of that element. But this is not the case with most of the nonmetals.  For example, a molecule of oxygen consists of two atoms of oxygen and hence it is known as a diatomic molecule, O2. If 3 atoms of oxygen unite into a molecule, instead of the usual 2, we get ozone. The number of atoms constituting a molecule is known as its atomicity.  Molecules of metals and some other elements, such as carbon, do not have a simple structure but consist of a very large and indefinite number of atoms bonded together. You may like Do I need car insurance? What is car insurance? How could I get cheaper car insurance? What is auto insurance? Why Adulterant food is the barrier to sound health? What are the producers? What are food preservatives? What is food chain? What is tertiary consumer?

What is a Molecule?

A molecule is in general a group of two or more atoms that are chemically bonded together, that is, tightly held together by attractive forces. A molecule can be defined as the smallest particle of an element or a compound that is capable of independent existence and shows all the properties of that substance. Atoms of the same element or of different elements can join together to form molecules. You may like Do I need car insurance? What is car insurance? How could I get cheaper car insurance? What is auto insurance? Why Adulterant food is the barrier to sound health? What are the producers? What are food preservatives? What is food chain? What is tertiary consumer?

How Do Atoms Exist?

Atoms of most elements are not able to exist independently. Atoms form molecules and ions. These molecules or ions aggregate in large numbers to form the matter that we can see, feel, or touch. You may like Do I need car insurance? What is car insurance? How could I get cheaper car insurance? What is auto insurance? Why Adulterant food is the barrier to sound health? What are the producers? What are food preservatives? What is food chain? What is tertiary consumer?

Dalton’s atomic theory

Image
According to Dalton’s atomic theory, all matter, whether an element, a compound, or a mixture is composed of small particles called atoms. The postulates of this theory may be stated as follows: All matter is made of very tiny particles called atoms. Atoms are indivisible particles, which cannot be created or destroyed in a chemical reaction. Atoms of a given element are identical in mass and chemical properties. Atoms of different elements have different masses and chemical properties. Atoms combine in the ratio of small whole numbers to form compounds. The relative number and kinds of atoms are constant in a given compound.  You will study in the next chapter that all atoms are made up of still smaller particles. You may like Do I need car insurance? What is car insurance? How could I get cheaper car insurance? What is auto insurance? Why Adulterant food is the barrier to sound health? What are the producers? What are food preservatives? What is food chain? What is tertiary consumer?

Properties of non-metal

Non-metals usually show some or all of the following properties: • They display a variety of colours. • They are poor conductors of heat and electricity. • They are not lustrous, sonorous, or malleable. Examples of non-metals are hydrogen, oxygen, iodine, carbon (coal, coke), bromine, chlorine etc. Some elements have intermediate properties between those of metals and non-metals, they are called metalloids; examples are boron, silicon, germanium, etc. You may like Do I need car insurance? What is car insurance? How could I get cheaper car insurance? What is auto insurance? Why Adulterant food is the barrier to sound health? What are the producers? What are food preservatives? What is food chain? What is tertiary consumer?

People Are Reading...

Branches of Biology

What is revolution?

What is sinking fund?

The Importance of Information and Communication Technology

Which branch of biology does genetics belong to?

Concept of Biology

What is thermometry?