### TED Theater, Soho, New York

Tuesday, September 24, 2019
New York, NY

## The Event

As part of Global Goals Week, the Skoll Foundation and the United Nations Foundation are pleased to present We the Future: Accelerating Sustainable Development Solutions on September 21, 2017 at TED Theater in New York.
The Sustainable Development Goals, created in partnership with individuals around the world and adopted by world leaders at the United Nations, present a bold vision for the future: a world without poverty or hunger, in which all people have access to healthcare, education and economic opportunity, and where thriving ecosystems are protected. The 17 goals are integrated and interdependent, spanning economic, social, and environmental imperatives.
Incremental change will not manifest this new world by 2030. Such a shift requires deep, systemic change. As global leaders gather for the 72nd Session of the UN General Assembly in September, this is the moment to come together to share models that are transforming the way we approach the goals and equipping local and global leaders across sectors to accelerate achievement of the SDGs.

Together with innovators from around the globe, we will showcase and discuss bold models of systemic change that have been proven and applied on a local, regional, and global scale. A curated audience of social entrepreneurs, corporate pioneers, government innovators, artistic geniuses, and others will explore how we can learn from, strengthen, and scale the approaches that are working to create a world of sustainable peace and prosperity.

Meet the

# Speakers

Click on photo to read each speaker bio.

Amina

### Mohammed

Deputy Secretary-General of the United Nations

Astro

### Teller

Captain of Moonshots, X

Catherine

### Cheney

West Coast Correspondent, Devex

Chris

Debbie

### Aung Din

Co-founder of Proximity Designs

Dolores

### Dickson

Regional Executive Director, Camfed West Africa

Emmanuel

### Jal

Musician, Actor, Author, Campaigner

Ernesto

### Zedillo

Member of The Elders, Former President of Mexico

Georgie

### Benardete

Co-Founder and CEO, Align17

Gillian

### Caldwell

CEO, Global Witness

Governor Jerry

### Brown

State of California

Her Majesty Queen Rania

Jordan

Jake

### Wood

Co-founder and CEO, Team Rubicon

Jessica

### Mack

Senior Director for Advocacy and Communications, Global Health Corps

Josh

### Nesbit

CEO, Medic Mobile

Julie

### Hanna

Executive Chair of the Board, Kiva

Kate Lloyd

### Morgan

Producer, Shamba Chef; Co-Founder, Mediae

Kathy

### Calvin

President & CEO, UN Foundation

Mary

### Robinson

Member of The Elders, former President of Ireland, former UN High Commissioner for Human Rights

Maya

### Chorengel

Senior Partner, Impact, The Rise Fund

Dr. Mehmood

### Khan

Vice Chairman and Chief Scientific Officer, PepsiCo

Michael

### Green

CEO, Social Progress Imperative

### Yunus

Nobel Prize Laureate; Co-Founder, YSB Global Initiatives

Dr. Orode

### Doherty

Country Director, Africare Nigeria

### Muthiah

CEO, Global Alliance for Clean Cookstoves

Rocky

### Dawuni

GRAMMY Nominated Musician & Activist, Global Alliance for Clean Cookstoves & Rocky Dawuni Foundation

Safeena

### Husain

Founder & Executive Director, Educate Girls

Sally

### Osberg

President and CEO, Skoll Foundation

Shamil

### Idriss

President and CEO, Search for Common Ground

Main venue

### TED Theater

Soho, New York

330 Hudson Street, New York, NY 10013

#### Email

wtfuture@skoll.org

Due to limited space, this event is by invitation only.

## Save the Date

That means that the position of equilibrium will move so that the temperature is reduced again. When a chemical system at equilibrium is disturbed, it returns to equilibrium by counteracting the disturbance. Le Chatelier’s Principle Definition. PCl 5(g) ⇌ PCl 3(g) + Cl 2(g) 1 Vol 1 Vol 1 Vol. 1. But decrease in temperature results in the decrease in the rate of reaction. The concentration of colorless $$\ce{N_2O_4}$$ increases, and the concentration of brown $$\ce{NO_2}$$ decreases, causing the brown color to fade. Addition of an inert gas. Chemical reactions accompanied by an increase in volume: Consider following reaction. This reduces the total pressure exerted by the system and reduces, but does not completely relieve, the stress of the increased pressure. 1 Herrlich, P. “The Responsibility of the Scientist: What Can History Teach Us About How Scientists Should Handle Research That Has the Potential to Create Harm?”. Le Chatelier's principle describes the response of a system in equilibrium to counteract the effects caused by an external agent. The LibreTexts libraries are Powered by MindTouch® and are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. Missed the LibreFest? If a system is at equilibrium, and we do something to it, it will shift in a particular way. However this does not affect the solid and pure liquid systems since their active masses are always taken as unity. this case, the system will try to increase the temperature. a) Write the equation for the equilibrium system. much lighter, as shown in the above image for the reaction at 0 oC. We have stressed this system by introducing additional $$\ce{H_2}$$. $$K = \dfrac{1}{[N_2]}$$; solid lithium does not appear in the equilibrium constant expression, so no compensatory change is necessary. To restore equilibrium, the reaction will in either forward or backward direction. Lesson organisation . Catalysts do not affect the position of an equilibrium; they help reactions achieve equilibrium faster. Le Principe de Le Chatelier, connu aussi sous le nom de "Loi générale de modération", implique que lorsqu'un système est soumis à une perturbation (comme une variation de concentration, de température ou de pression), il réagit et atteint un nouvel état d'équilibre en s'opposant à la perturbation de manière à en atténuer ses effets. Hence temperature of 773K is maintained and iron is used as catalyst. Equilibrium and Le Chatelier's Principle ©POGIL 2005, 2006Authored by M. Chiolo; Revised by E. Graham, L. Giloni and Ellen Kannengieser Edited by Linda Padwa and David Hanson, Stony Brook University7/7 ©POGIL 2005, 2006 Ammonium nitrate has also been used in explosives, including improvised explosive devices. The stress is relieved when the reaction shifts to the right, using up some (but not all) of the excess $$\ce{H_2}$$, reducing the amount of uncombined $$\ce{I_2}$$, and forming additional $$\ce{HI}$$. Derivation of van 't Hoff equation for temperature dependence of equilibrium constant. Le Chatelier's principle. The availability of nitrogen is a strong limiting factor to the growth of plants. The concentrations of both reactants and products then undergo additional changes to return the system to equilibrium. When hydrogen reacts with gaseous iodine, heat is evolved. On the other hand, a decrease in the pressure on the system favors decomposition of $$\ce{NO_2}$$ into $$\ce{NO}$$ and $$\ce{O_2}$$, which tends to restore the pressure. However, we can qualitatively predict the effect of the temperature change by treating it as a stress on the system and applying Le Chatelier's principle. 1. Equilibrium and Le Chatelier's Principle. The reaction is exothermic, so lowering the temperature will favour forward reaction. Equilibrium and Le Chatelier's Principle. To determine the effect of temperature on a reaction, first write the equation the right of the equilibrium sign will go up, and everything on the left side will go Le Chatelier's principle (also known as "Chatelier's principle" or "The Equilibrium Law") states that when a system experiences a disturbance (such as concentration, temperature, or pressure changes), it will respond to restore a new equilibrium state. Figure: A rise in temperature causes more particles to have energy greater than the activation energy. Exactly the opposite will happen if we decrease the When we change the temperature of a system at equilibrium, the equilibrium constant for the reaction changes. 2. 12. The generalization is known as Le-Chatelier’s Principle. This principle was named after Henry Louis Le Chatelier and Karl Ferdinand Braun. He stands as an example of the ethical dilemmas that face scientists in times of war and the double-edged nature of the sword of science. 1 Vol 2 Vol. Chemical reactions accompanied by an increase in volume: According to Le Chatelier’s principle, adding additional reactant to a system will shift the equilibrium to the right, towards the side of the products. Watch the recordings here on Youtube! an increase in temperature. energy term must increase. energy term must decrease. Changing the temperature of a system at equilibrium has a different effect: A change in temperature actually changes the value of the equilibrium constant. You should be comfortable doing basic equilibrium calculations in order to understand this material. e) Increased temperature f) Decreased temperature 3. Changing concentration or pressure perturbs an equilibrium because the reaction quotient is shifted away from the equilibrium value. Chemical equilibria and Le Chatelier's principle. $$\ce{6Li (s)} + \mathbf{N_2(g)} \ce{ \rightleftharpoons 2Li3N(s)}$$: the amount of $$\ce{Li}$$ is tripled. $$\textbf{n-butane}_{(g)} \rightleftharpoons isobutane_{(g)}$$: the concentration of isobutane is halved. Iodine crystals are in equilibrium with iodine vapour. The reaction will shift to the left. As we saw in the previous section, reactions proceed in both directions (reactants go to products and products go to reactants). (9.6.6) N 2 O 4 (g) + heat ⇌ 2 NO 2 (g) Dinitrogen tetroxide (N 2 O 4) is colorless, while nitrogen dioxide (NO 2) is dark brown in color. The term "shift" is what nature does to keep the system at equilibrium. $$\mathbf{SO_2(g)} + \ce{ Cl2(g) \rightleftharpoons SO2Cl2(l)}$$: the concentration of $$\ce{Cl2}$$ is doubled. Changing the chlorine concentration or the temperature shifts the position of equilibrium in accordance with Le Chatelier’s principle. The law may be stated: When a system at equilibrium is subjected to a change in temperature, volume, concentration, or pressure, the system readjusts to partially counter the effect of the change, resulting in a new equilibrium. Remember that the system $$NH_4HS_{(s)} \rightleftharpoons \mathbf{NH}_{3(g)} + H_2S_{(g)}$$: the concentration of $$H_2S$$ is tripled. Changing the temperature of a system at equilibrium has a different effect: A change in temperature actually changes the value of the equilibrium constant. In this experiment we will use two separate methods to disturb systems at chemical equilibrium. pressure (for gaseous reactants) It is important to understand what effect a change in one of these factors will have on a system that is in chemical equilibrium. The direction of shift can be predicted for changes in concentrations, temperature, or pressure. Application of Le-Chatelier’s Principle to Manufacture of Ozone: $$K = \dfrac{[H_2]}{[HBr]}$$; $$[H_2]$$ must decrease by about a factor of 3. Excess chlorine converts this to yellow, solid, iodine trichloride, setting up a heterogeneous equilibrium between these three substances. s principle states that if a dynamic equilibrium is disturbed by changing the conditions (such as concentration Large quantities of ammonia are converted to nitric acid, which plays an important role in the production of fertilizers, explosives, plastics, dyes, and fibers, and is also used in the steel industry. We next address what happens when a system at equilibrium is disturbed so that $$Q$$ is no longer equal to $$K$$. How Le Chatelier's Principle can be used to predict the effect of disturbances to equilibrium? Identify how each substance will respond to this change, using the The overview of how different disturbances affect the reaction equilibrium properties is tabulated in Table $$\PageIndex{1}$$. The principle is named after the French chemist Henry Louis Le Chatelier. source : Grade 12uchem.weebly.com. By Le-Chatelier’s principle, at a constant temperature, increase in pressure will favour a reaction which is accompanied by a decrease in volume and decrease in pressure will favour a reaction which is accompanied by the increase in volume. Le Chatelier's principle is commonly observed in chemical reactions. Temperature. Each year, ammonia is among the top 10 chemicals, by mass, manufactured in the world. 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