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Posted by Devansh Tiwari 5 years ago (10267494)
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Posted by Harshith Kumar.S 5 years ago (9566525)
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Posted by Vaus Yadav 5 years ago (10341608)
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Laxyata Kanwar 4 years, 10 months ago (9497474)
Charvee Ghanghas 4 years, 10 months ago (10616573)
Yogita Ingle 5 years ago (2577571)
जो चिड़िया काफ़ी तेज़ आवाज़ में बोलती है और उसकी पूँछ के नीचे वाली जगह लाल होती है, तो समझना चाहिए कि वह चिड़िया बुलबुल है। बुलबुल की पूँछ के सिरे का रंग सफेद होता है। उसका बाकी शरीर भूरा और सिर का रंग काला होता है। बुलबुल तेज़ आवाज़ में बोलती है तथा उसे मनुष्य से बिलकुल ही डर नहीं लगता।
Posted by Gaurav Kumar Gupta 4 years, 6 months ago (9263840)
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Posted by Aastha Bhurani 5 years ago (9786104)
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Bhumika Jaiswal 4 years, 11 months ago (9565070)
Posted by Nihal Gupta 5 years ago (10226418)
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Posted by Pooja Jain 5 years ago (10303886)
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Yogita Ingle 5 years ago (2577571)
Common physical features of alkali metals:
(1) They are soft and can be easily cut.
(2) They have silvery white appearance. They are light coloured.
(3) Due to large atomic size, they have low density. On moving down the group the density increases with exception of K which has lower density than Na.
(4) Due to weak metallic bonding, alkali metals have low melting and boiling points.
(5) They provide characterisitc colour to flames.
(6) They show photoelectric effect. On irradiation with lightCs and K lose electrons.
Common chemical features of alkali metals:
Due to low ionization enthalpy, akali metals have high reactivity.
On moving down the group, the reactivity increases.
(1) On reaction with water, oxides and hydroxides are formed.
On moving down the group, the reaction becomes more and more vigorous.
(2) On reaction with water, hydroxide and hydrogen are formed.
2M+2H2O→2MOH+H2
(3) On reaction with hydrogen, hydrides are formed.
2M+H2→MH
(4) They directly combine with halogens to form ionic halides. Li is an exception.
2M+Cl2→2MCl,(M=Li,K,Rb,Cs)
(5) They are strong reducing agents. On moving down the group, the reducing power increases with exception of Li. Due to high hydration energy, Li is the strongest reducing agent among alkali metals.
(6) They dissolve in liquid ammonia. The solution is deep blue in colour due to presence of ammoniated electrons.
Posted by Abhishek Yadav 5 years ago (10010870)
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Mohamed Fazil 5 years ago (12319295)
Posted by Himanshu Yadav 5 years ago (9815835)
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Mayank Singhal 5 years ago (9895859)
Niral Dharawat 5 years ago (10334642)
</a>Posted by Royal Thakur ? 5 years ago (9579994)
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First Name 5 years ago (10129186)
Posted by Royal Thakur ? 5 years ago (9579994)
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Posted by Vaishnavi Singh 5 years ago (10347567)
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Posted by Vansh Dureja 5 years ago (10225012)
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Posted by Royal Thakur ? 5 years ago (9579994)
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Posted by Shubham Kumar Modanwal 5 years ago (9433872)
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Yogita Ingle 5 years ago (2577571)
Relative density of gold = ρ(gold)/ρ(water) = 19.32/1 = 19.32
Posted by Vandana Negi 5 years ago (10350670)
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Posted by Anu Panday Panday 5 years ago (10345070)
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Abirami Kamalbabu 4 years, 11 months ago (10036453)
Posted by Vaus Yadav 5 years ago (10341608)
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Posted by Ńâncÿ Mîzë 5 years ago (10350655)
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Anshika Nagar 4 years, 11 months ago (5860089)
Yogita Ingle 5 years ago (2577571)
The first Mesopotamian tablets, written around 3200 BCE, contained picture-like signs and numbers. Writing began when society needed to keep records of transactions – because in city life transactions occurred at different times, and involved many people and a variety of goods.
Posted by Aniket Dhiman 5 years ago (9860552)
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Posted by Taran Tpk 5 years ago (10350634)
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Yogita Ingle 5 years ago (2577571)
Given that, the point P(2,1) lies on the line segment joining the points A(4,2) and 8(8, 4), which shows in the figure below:
Posted by Christian Herry 5 years ago (10350595)
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Posted by Deepanshi Saini 5 years ago (10350385)
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Yogita Ingle 5 years ago (2577571)
(i) Men and women walking across the statue of liberty offering homage.
(ii) Statue of liberty has a torch of enlightenment and Charter of the Rights of Man.
(iii) On the Earth lie the shattered remains of the symbols of absolutist institutions.
Posted by Chhavi Sonkusre 5 years ago (9672518)
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Posted by Jinam Khandhar 5 years ago (7361817)
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Yogita Ingle 5 years ago (2577571)
When the food particle is completely trapped inside its vacuole amoeba secretes its digestive enzymes and digests the food.
The digestive enzymes are secreted into the food vacuole in amoeba to break down the food.
Posted by Dev Solanki 5 years ago (10180498)
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Yogita Ingle 5 years ago (2577571)
वृद्धिरेचि’ सूत्र द्वारा संहिता के विषय में अ/आ वर्ण से परे ‘एच’ (ए, ओ, ऐ, औ) (स्वर) होने पर पूर्व एवं पर के स्थान पर वृद्धि संधि एकादेश (आ, ऐ, औ) होते हैं। इनके क्रमशः
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