Metals And Non-Metals | Fact & Information

Metals and Non-metals

Elements can be grouped into two broad categories-metals and non-metals. Metals are elements that are Opaque, lustrous, and good conductors of heat and electricity. lron, gold, and silver are common metals.

Non-metals are elements that cannot conduct electricity or heat very well. Examples of non-metals are oxygen, hydrogen, and carbon. Only 18 elements in the periodic table are generally considered non-metals while there are over 80 metals.

Properties of metals

° Metals have lustre. They are shiny when cut, scratched, or polished.

° They are malleable, that is, they can be hammered into thin sheets without breaking.

° They are good conductors of electricity and heat.

° They are ductile, that is, they can be melted and drawn into thin wires.

° All metals except mercury are solid at room temperature.

° Most metals have high melting points.




Properties of non-metals

° Non-metals have no lustre, that is, they have a dull appearance.

° They are poor conductors of heat and electricity.

° They are brittle, that is, they break easily.

° They are neither ductile nor malleable.

° They have low density and low melting points.


Noble metals

Noble metals are pure metals.They are non reactive and do not combine with other elements to form compounds.They donor corrode easily. Noble metals include copper, palladium, silver, platinum and gold. They are ideal for jewellery and coins.


Alkali metals

Alkali metals are very reactive. They have low melting points. They are soft enough to be cut with a knife. Potassium and sodium are two examples of alkali metals.


Application of metals

There are numerous applications of metals. They are used in building, transportation, aerospace technology, computers, and other electronic devices, satellites, and biomedical applications. They are also used in farming and agriculture in tractors, combines, planters, etc. They are commonly used in household appliances such as vacuum cleaners, pumps, water heaters, ovens, dish washers, washing machines, microwaves, refrigerators, etc. Metals are also used for electric power production and distribution. Boilers, turbines, generators, transformers, power lines, nuclear reactors, oil wells, and pipelines
use metals.



Poor metals

Poor metals become useful only when added to other substances poor metals include aluminium, gallium, tin, thallium, antimony, and bismuth.


Metals of antiquity

Metals were discovered around 5,000 years ago. Cold and copper were one of the earliest metals to be discovered. Seven metals, known as metals of antiquity, were metals upon which ancient civilizations were based. These metals were known to the Mesopotamians, Egyptians, Greeks, and the Romans.The seven metals were: gold (6000 BC), copper (4200 BC), silver (4000 BC), lead (3500 BC), tin (1750
BC), iron (1500 BC), and mercury (750 BC).


Metalloids

Metalloids have properties of both metals and non-metals. Some metalloids such as silicon and germanium are semi-conductors.

Alkaline earth metals

Alkaline earth metals are found in compounds with many different minerals. They are less reactive than alkali metals. They are harder and have higher melting points. Calcium, magnesium, and barium are common examples of alkaline earth metals.


Transition metals

Transition elements commonly refer to any element in the d-block of the periodic table. They include zinc, cadmium, and mercury. All transition elements are metals.Therefore, they are also called transition metals.They are hard, shiny strong, and easy to shape. They are used for many industrial purposes.

Who invented the thermometer?

The first recorded thermometer was produced by the Italian, Santorio Santorio (1561-1636) who was one of a group of Venetian scientists working at the end of the Sixteenth Century. As with many inventions the thermometer came about through the work of many scientists and was improved upon by many others.

1596 Galileo Galilei and the first thermoscope

Galileo Galilei is often claimed to be the inventor of the thermometer. However the instrument he invented could not strictly be called a thermometer: to be a thermometer an instrument must measuretemperature differences; Galileo's instrument did not do this, but merely indicated temperature differences. His instrument should rightly be called a thermoscope.

The Thermoscope
The predecessor to the thermometer, the thermoscope is a thermometer without a scale; it indicates differences in temperature only ie it can show if the temperature is higher, lower or the same, but unlike a thermometer it cannot measure the difference nor can the result be recorded for future reference. The thermoscope was widely used by a group of scientists in Venice that included Galileo. It was only a small step from the thermoscope to the thermometer.

1612 Santorio Santorio - the first thermometer

The Italian, Santorio Santorio (1561-1636) is generally credited with having applied a scale to an air thermoscope at least as early as 1612 and thus is thought to be the inventor of the thermometer as a temperature measuring device. Santorio's instrument was an air thermometer. Its accuracy was poor as the effects of varying air pressure on the thermometer were not understood at that time.

1654 The first sealed liquid-in-glass thermometer

The sealed liquid-in-glass thermometer, more familiar to us today, was first produced in 1654 by the Grand Duke of Tuscany, Ferdinand II (1610-1670). His thermometer had an alcohol filling. Although this was a significant development his thermometer was inaccurate and there was no standardised scale in use.

1714 The first mercury thermometer

Gabriel Fahrenheit (1686-1736) was the first person to make a thermometer using mercury. The more predictable expansion of mercury combined with improved glassworking techniques led to a much more accurate thermometer.

Fahrenheit - the first Standard Thermometer Scale

Fahrenheit used the newly discovered fixed points to devise the first standard temperature scale for his thermometer. Fahrenheit divided the freezing and boiling points of water into 180 degrees. 32 was chosen as the the figure for the lower fixed point as this produced a scale that would not fall below zero even when measuring the lowest possible temperatures that he could produce in his laboratory - a mixture of ice, salt and water. It is sometimes suggested that Fahrenheit divided his scale into 100 degrees using blood temperature (incorrectly measured) and the freezing point of water as fixed points - this is not true. The Fahrenheit scale is still in use today.

1731 The Réamur Scale

In 1731 the Frenchman, René Antoine Ferchauld de Réamur (1683-1757) proposed a thermometer scale on which the freezing point of water was 0° and the boiling point was 80°. The Réamur scale is not in use today.

1742 The Celsius Scale

In 1742 a Swedish scientist named Anders Celsius (1701-1744) devised a thermometer scale dividing the freezing and boiling points of water into 100 degrees. Celsius chose 0 degrees for the boiling point of water, and 100 degrees for the freezing point. A year later, the Frenchman Jean Pierre Cristin (1683-1755) inverted the Celsius scale to produce the Centigrade scale used today (freezing point 0°, boiling point 100°). By international agreement in 1948 Cristin's adapted scale became known as Celsius and is still in use today.

1848 The Absolute Temperature Scale or Kelvin Scale

In 1848 Sir William Thomson, Baron Kelvin of Largs, Lord Kelvin of Scotland (1824 - 1907) proposed the absolute temperature scale with zero degrees being the theoretical lowest temperature possible where molecular motion ceases. Kelvin defined 1 Kelvin degree as being equal to one Celsius. The Degree Kelvin is the current Standard Unit of temperature measurement.

Ma Huri Ma Diyo By Ram Krishna Dhakal:You Can Click And See This Video

Ma Huri Ma Diyo is a new Nepali romantic aadhunik sentimental pop song from Album “Aawaran”. The music video features by Nirajan Thapa , Puja Giri, Raaz Neupane, Babina Poudel, Bhola Shrestha and Anuja Udhas. Ma Huri Ma Diyo is a Nepali song by Ramkrishna Dhakal which is directed by Nikesh Khadka. Ma Huri Ma Diyo music video was edited by Nishan Ghimire and music video was cinematographed by Utsav Dahal.

यी कुराहरु बुझनुस् कुनै मन्दिर,देविदेउता पुज्नु पर्दैन।

मानव जिबनका लागि महत्त्वपूर्ण सुत्रहरु।

१.सम्मान गर्नु-माता,पिता र गुरुलाई।

२.पर्खदैन-समय,मृत्यु,ग्राहक।

३.सानो नसम्झनु-रोग,कर्जा र शत्रुलाई।

"उद्देश्य के लिनु उडि छुनु चन्द्र एक",आफ्नो लक्ष्यलाई कसरी प्राप्त गर्ने त?

आजको व्यस्त जीवनशैलिले गर्दा मानिसहरुलाई भागदौडमा हिड्दैमा ठिक्क परेको छ,कतिपय मानिसहरु कुनै काम नपाएर समय खेर फालिरहेका छ्न् त कतिपय मानिसहरु जिन्दगिको कुनै उद्देश्य नदेखेर त्यत्तिकै भौतारिरहनुपरेको अबस्था छ, राम्रो सँग केही कुरा नयाँ सोच्ने विषयमा समेत हम्मेहम्मे परेको छ जसले गर्दा हामिभित्र निराशापनले छाएको छ।हामिलाई आफ्नै बारेमा पनि राम्ररी सोच्ने फुर्सद भएको छैन।आउनुस् मित्रहरु निराशाबाट बच्नको लागि तलका कुरा दैनिक व्यवहारमा लागू गर्नुसहोस्।

स्याउ खानलाई नमान्नुस झ्याउ।

साधरणतया हाम्रो शरिरलाई स्वस्थ राख्नको लागि फलफुलको सेवन गर्नु एकदम लाभदायपुर्ण छ।फलफुलहरुमध्य पनि स्याउको महत्त्व खासगरी उत्तिकै हाम्रो स्वस्थ शरिरको लागि एकदम लाभदायक छ।यसका फाईदाहरु तल उल्लेखित गरिएको छ।

१.एकदाना स्याउको नियमित सेवन गर्नाले मस्तिष्कको कमजोरी,निन्द्रा,वात,पित्त,मिर्गौला र कलेजो सम्बन्धी सम्पुर्ण रोगहरुमा ठूलो लाभ पुर्याउछ।

२.प्रशस्त मात्रामा भिटामिन बि पाईने हुँदा यो शितल,पौष्टिक छ,विर्यबर्द्द्क र सुपाच्य छ।

ध्यान(Meditation) भनेको के हो त? (कृष्ण भगवानको महान सिर्जना)भगबान देख्न खोज्नु मुर्खता हो भने महसुस गर्न खोज्नु महानता हो।

बास्तबमा ध्यान भनेको हाम्रो मन इन्द्रियहरुलाई काबुमा राख्ने कला नै हो।यो कला जन्मेदेखिनै हर मानिसहरुले लिएर आएका हुन्छन्।तर हाम्रो यस संसारको मायावी सृष्टिले गर्दा हाम्रो मनलाई काबुमा गर्न सकिँदैन।

एउटा सत्य"हाम्रो यस ब्रमाण्डका नायक तथा निर्देशक श्रीकृष्ण भगवानको निर्देशनमा नै यो सारा विश्व ब्रमाण्डको उत्पती भएको छ,उहाँले नै यो माया भन्ने भावुक तत्त्व यस सँसारमा छोडदिनुभएको छ,जुन दिन उहाँले यो छरिएको मायालाई