Explanation:
The 2019 water crisis in Chennai has made us realize the importance of saving water more than ever. Water, as we all know, is a finite resource without which our planet would be a barren wasteland. Today with our increasing population it would be logical to say that our water consumption has also increased. And with increasing demand and lesser supply, water scarcity arises. Our ancestors who had foreseen the potential dangers of water scarcity had developed methods to conserve water that was suited for the varied terrain of the Tamil-speaking kingdoms.
Traditional Rainwater Conservation methods of Tamil Nadu
Eri
There are no perennial rivers in Tamil Nadu except the Thamirabharani River which flows through Thirunelveli district. And so, several hundred years ago a simple system was devised to utilize the rainwater to the fullest. An Eri or tank system is one of the oldest forms of water conservation systems in India. Many Eris are still in use in Tamil Nadu and play an active role in irrigation. They act as water reservoirs and flood control systems. They prevent soil erosion, recharge groundwater, and prevent wastage of runoff water during heavy rainfall.
Kudimaramathu
Kudimaramathu is one of the old traditional practice of stakeholders participating in the maintenance and management of irrigation systems. During earlier days, citizens of a village used to actively participate in maintaining the water bodies of their village by deepening and widening the lakes and ponds and restoring the water bodies back to their original form. The silt, rich in nutrients, collected in the process would be used by the farmers themselves in their field. A sense of collective ownership ensured the continued survival of the water bodies.
Ur ans is option d
addition
Global Warming has been increased by living organisms like animals and humans by many ways:
1) We burn fossil fuels, which is very bad for our Environment's health
2) Animals like cows & buffalo produces a lot of methane which causes Global Warming.
3) Animals cut a lot of trees for their products, so increase the amount of Carbon dioxide in the atmosphere, thus increases Global Warming.
4) We don't minimize our dependence on Non-renewable source of energy which 'causes a lot of pollution in the environment
Hope this helps!
Answer:
Zinc, Cerio, Talio, Cloro y Criptón.
Explicación:
El zinc es el elemento que tiene el número atómico 30 y su símbolo es Zn. Se encuentra en el grupo 2B de la tabla periódica. El cerio es el elemento que tiene el número atómico 58 y su símbolo es Ce. Se encuentra en el grupo de lantánidos de la tabla periódica. El talio es el elemento que tiene el número atómico 81 y su símbolo es Tl. Se encuentra en el tercer grupo de la tabla periódica. El cloro es el elemento que tiene el número atómico 17 y su símbolo es Cl. Se encuentra en el séptimo grupo de la tabla periódica. El criptón es el elemento que tiene el número atómico 36 y su símbolo es Kr. Se encuentra en el grupo de gases nobles, es decir, en la tabla periódica del octavo grupo.
Answer is: Kb for methylamine is 4.37·10⁻⁴.<span>
Chemical reaction: CH</span>₃NH₂ + H₂O → CH₃NH₃⁺ + OH⁻.
c(CH₃NH₂) = 0.253 M.
α = 4.07% ÷ 100% = 0.0407.
[CH₃NH₃⁺] = [OH⁻] = c(CH₃NH₂) · α.
[CH₃NH₃⁺] = [OH⁻] = 0.253 M · 0.0407.
[CH₃NH₃⁺] = [OH⁻] = 0.0103 M.
[CH₃NH₂] = 0.253 M - 0.0103 M.
[CH₃NH₂] = 0.2427 M.
Kb = [CH₃NH₃⁺] · [OH⁻] / [CH₃NH₂].
Kb = (0.0103 M)² / 0.2427 M.
Kb = 4.37·10⁻⁴.