26/12/2021
Class 10th
Term 2
Carbon and compound
When you know better , you do better
26/12/2021
Class 10th
Term 2
Carbon and compound
15/11/2021
Class 10th
Metals and Non-metals
Quick revision
04/11/2021
Happy diwali to all of you
28/10/2021
How Do You Make Fireworks of Different Colors?
Two thousand years ago, a cook mixed three ingredients very common in any kitchen: potassium nitrate (food preservative), sulphur and charcoal. Mixed and and heated, they go off exploding on a huge bang. This is basically gunpowder.
If this mixture is put on a cane, pressure builds up giving rise to a bigger explosion. Originally, potassium nitrate was used. Potassium cations are responsible of a white color. If different salts are used instead, with different metals as cations, you get the different colors. For example, strontium salts give red colors. Iron compounds give gold-colored fireworks. Also, sodium gives yellow, barium gives green and copper gives blue.
Do you know DNA doesn't catch fire..
Its chemical structure makes it ideal for stopping fires. Remember, DNA is made of an alternating phosphate-and-sugar backbone with nitrogen bases (the A, T, G, C).
1. When heated, the phosphate-containing backbone produces phosphoric acid, which chemically removes water from cotton fibers. This leaves behind a flame-resistant, carbon-rich residue.
2. The nitrogen-containing bases release ammonia, which dilutes flammable gases and inhibits combustion reactions. They also help turn the carbon-rich deposits into a slow-burning protective layer.
Water turns solid at 20 degrees, if it contains methane. They must be mixed together at high pressure. Then water and methane sometimes form gaseous hydrate, which at a temperature of up to 20 degrees resembles packed snow.
मेथेन होने पर पानी 20 डिग्री पर ठोस हो जाता है। उन्हें उच्च दबाव पर एक साथ मिलाया जाना चाहिए। फिर पानी और मीथेन कभी-कभी गैसीय हाइड्रेट बनाते हैं, जो 20 डिग्री तक के तापमान पर पैक्ड बर्फ जैसा दिखता है।
Rakhi is the covalent bond between brother and her sister,
Who share pair of electron of LOVE❤
Hydrogen was the first chemical element that appeared at the beginning of the universe’s existence. All the hydrogen in the world has existed since that time, and new hydrogen has not appeared. This means that the age of every atom of hydrogen in the world, including those in the human body, is around 13.5 billion years old. A little later, as a result of nuclear synthesis some hydrogen atoms became atoms of helium, carbon and so on. But around 75% of the mass of the visible universe still consists of hydrogen. Helium accounts for another 25%, and all the other remaining elements for just 2%. But on Earth, the mass of hydrogen and helium put together does not exceed 1% of the total elements.
Ques:-Do you know ? If you mix 50 ml of water with 50 ml of ethanol, the total volume actual equals less than 100 ml.
क्या आप जानते हैं ? यदि आप 50 मिलीलीटर इथेनॉल के साथ 50 मिलीलीटर पानी मिलाते हैं, तो कुल मात्रा वास्तविक 100 मिलीलीटर से कम होती है।
Ans:- Because the molecules that make up ethanol are smaller than the molecules that make up water. So, the ethanol molecules cram themselves between the water molecules. As a result, the volume is less than expected. The volume adds up to approximately 96 ml. Example:-a container of sand poured into a container of rocks. The sand fills in the empty spaces between the rocks.
As the volume decreases, the density increases for the same mass. As the molecules pack tighter together, the solution becomes more dense.
क्योंकि इथेनॉल बनाने वाले अणु पानी बनाने वाले अणुओं से छोटे होते हैं। इसलिए इथेनॉल के अणु पानी के अणुओं के मध्य चले जाते है। जिससे विलयन की मात्रा अपेक्षाकृत कम हो जाती है। जिसकी मात्रा लगभग 96 मिलीलीटर होती है। जैसे रेत के एक कंटेनर को चट्टानों के कंटेनर में डाला जाता है। रेत चट्टानों के बीच खाली जगहों में भर जाती है।
जैसे ही मात्रा घटती है, उसी द्रव्यमान के लिए घनत्व बढ़ता है। जैसे-जैसे अणु एक साथ सख्त होते जाते हैं, घोल अधिक सघन होता जाता है।
If you leave Earth at the age of 15 in a spaceship at the speed of light and spend 5 Years in space, when you get back on Earth you will be 20 years old and all your friends who were 15 when you left will be 65 years old. This phenomenon is known as "Time Dilation" in Physics.
यदि आप प्रकाश की गति से अंतरिक्ष में जाने के लिए 15 वर्ष की आयु में पृथ्वी छोड़ते हैं और 5 साल अंतरिक्ष में बिताते हैं, तो जब आप पृथ्वी पर वापस आते हैं तो आप 20 वर्ष के होंगे और आपके सभी दोस्त जो 15 वर्ष के थे, उनकी आयु 65 वर्ष होगी। इस घटना को भौतिकी में "समय अंतराल" के रूप में जाना जाता है
Humans are made of atoms – billions and billions of them. But atoms themselves are nearly all made of nothing – pure empty space. Apart from the electrons, the protons, and the neutrons, they are in fact 99.9% space are vacant in atom .They are held together only by waves and atomic forces.
But If you were, somehow, to remove the space between all these little particles in the atom, they would be even tinier that all the atoms in all the people in the world could fit on a spoon.there are roughly about 10⁸⁰ atoms in universe.
मनुष्य परमाणुओं से बना है - अरबों और अरबों परमाणु के संयोजन से। लेकिन परमाणु के मध्य कुछ नहीं होता हैं इलेक्ट्रॉनों, प्रोटॉन और न्यूट्रॉन के अलावा, वास्तव में 99.9% परमाणु में खाली स्थान होता हैं। वे केवल तरंगों और परमाणु बलों द्वारा एक दूसरे से जुड़े होते हैं।
लेकिन यदि किसी तरह से परमाणु में उपस्थित इलेक्ट्रॉनों, प्रोटॉन और न्यूट्रॉन के कणों के मध्य उपस्थित खाली स्थान को हटा दिया जाए तो इतने छोटे हो जायेंगे दुनिया के सभी लोगो में उपस्थित समस्त परमाणुओं को एक चम्मच पर रखा जा सकता हैं। समस्त ब्रह्मांड में लगभग 10⁸⁰ परमाणु हैं।
Q:-Can you freeze air ?
Ans:-Yes, you can. Air is mainly a mixture of nitrogen gas (N2) and oxygen gas (O2). Their freezing points are -210 °C and
-219 °C respectively, so below -220 °C, air would freeze. This has been achieved by using liquid helium. Helium, however, is the only known gas that does not freeze. Helium liquefies at -270 °C.