All questions of April Week 4 for Class 10 Exam

This is a natural indicator which are found in the nature of the plants

Methyl orange is a pH indicator frequently used in titration because of its clear and distinct colour variance at different pH values. Methyl orange shows pink colour in acidic medium and yellow colour in basic medium. Because it changes colour at the pH of a mid strength acid, it is usually used in titration for acids. Unlike a universal indicator, methyl orange does not have a full spectrum of colour change, but it has a sharp end point.

It is the property acid that ..... when acid react with metal carbonates ....acid + metal carbonates -------> salt +carbon dioxide + water .... so option B is correct.......

**Turmeric as a Natural Indicator**

Turmeric, a commonly used spice in cooking, can also be used as a natural indicator to detect the presence of bases. The active compound in turmeric responsible for this property is called curcumin. When curcumin comes into contact with bases, it undergoes a chemical reaction that results in a change in color. In the presence of bases, turmeric turns bright red.

**Explanation**

Turmeric contains a class of compounds known as polyphenols, which are responsible for its vibrant yellow color. Curcumin, one of the polyphenols present in turmeric, acts as a pH indicator. pH indicators are substances that change color depending on the acidity or alkalinity (basicity) of a solution.

Bases are substances that can accept protons or donate hydroxide ions (OH-) in a chemical reaction. When a base is added to a solution of turmeric, the curcumin molecules react with the base, resulting in the formation of a new compound. This new compound has a different structure and absorbs light in a different range of wavelengths, giving rise to a change in color.

In the case of turmeric, the reaction with bases leads to the formation of a red compound. This compound is responsible for the bright red color observed when turmeric comes into contact with bases. The exact mechanism of this reaction is complex and involves multiple steps, including the deprotonation of curcumin and the formation of a conjugated system.

**Conclusion**

In conclusion, turmeric can be used as a natural indicator to detect the presence of bases. When turmeric is exposed to bases, it undergoes a chemical reaction that results in a change in color. The active compound in turmeric, curcumin, reacts with bases to form a red compound, giving turmeric a bright red color in the presence of bases.

The period after WWII was marked by economic stability and rapid growth, largely driven by reconstruction efforts and technological advancements.

Multinational corporations (MNCs) moved to Asia to take advantage of cheaper labor, reducing production costs.

Significant Impact of the Industrial Revolution on Food Availability
The Industrial Revolution brought about transformative changes in various sectors, including agriculture and food distribution. One of the most significant impacts was the development of refrigerated ships, which revolutionized the way food was transported and made available to consumers.
Enhanced Food Preservation
- Refrigerated ships allowed for the long-distance transportation of perishable goods.
- This innovation enabled countries to import and export food items that would otherwise spoil quickly.
Increased Food Variety
- With refrigeration, a wider variety of foods became accessible year-round.
- Consumers enjoyed fresh fruits, vegetables, and meats from different regions, regardless of the season.
Global Trade Expansion
- The ability to ship perishable goods over long distances opened new markets.
- This led to an increase in international trade, enhancing food availability across countries.
Improved Food Security
- Refrigeration helped stabilize food supply by reducing spoilage and waste.
- Communities could rely on a steady supply of fresh food, contributing to overall food security.
Conclusion
In summary, the development of refrigerated ships during the Industrial Revolution significantly impacted food availability. It not only improved food preservation and expanded variety but also facilitated global trade and enhanced food security. This innovation marked a pivotal shift in how people accessed and consumed food, shaping modern dietary habits.

Consequences of the Abolition of the Corn Laws
The decision to abolish the Corn Laws in 1846 had significant consequences, particularly impacting trade and agriculture in Britain.
Overview of the Corn Laws
- The Corn Laws were tariffs and trade restrictions on imported grain.
- They aimed to protect domestic producers by keeping grain prices high.
Impact on Trade
- Abolishing the Corn Laws opened up the British market to imported grains, particularly from countries like America and Russia.
- This increased competition led to lower prices for food, benefiting consumers and enhancing their purchasing power.
Effect on Agriculture
- Although some domestic farmers faced challenges due to increased foreign competition, the overall agricultural sector had to adapt and innovate.
- Farmers began to diversify their crops and improve efficiency to compete with cheaper imports.
Strengthening of Local Economies
- Lower food prices resulted in increased disposable income for workers and consumers.
- This stimulated local economies as people had more money to spend on goods and services, boosting various sectors beyond agriculture.
Conclusion
- The abolition of the Corn Laws ultimately facilitated a transition towards a more modern agricultural and trading system.
- It promoted a free-market approach that encouraged efficiency and competitiveness, benefiting the economy as a whole.
By understanding these dynamics, we can appreciate how the decision to abolish the Corn Laws was pivotal in shaping modern economic policies and agricultural practices in Britain.

What is the G-77?
The G-77, or Group of 77, is a coalition of developing countries established in 1964. It was formed to promote their collective economic interests and enhance their negotiating capacity in the United Nations.
Background
- The G-77 began with 77 member countries, but it has since expanded to include over 130 developing nations.
- The group emerged during the first United Nations Conference on Trade and Development (UNCTAD) in Geneva.
Objectives of G-77
- Promote Economic Growth: The primary aim is to foster economic development and reduce poverty among member countries.
- Strengthen Negotiating Power: By working together, developing countries can have a stronger voice in international economic discussions and negotiations.
- Advocate for Fair Trade: The G-77 seeks to address the imbalances in global trade practices that often disadvantage developing nations.
Key Activities
- Policy Formulation: The G-77 works on formulating policies that address the specific needs of developing countries in international forums.
- Capacity Building: It provides a platform for technical cooperation and capacity-building initiatives among member states.
- Collaboration on Global Issues: The group collaborates on various global issues like climate change, sustainable development, and the digital economy.
Conclusion
In summary, the G-77 is a coalition of developing countries focused on promoting their economic interests and enhancing their influence in international affairs. Its efforts aim to create a more equitable global economic environment.

Rinderpest, a livestock disease, caused widespread cattle deaths, devastating local economies and livelihoods dependent on animal farming.

The NIEO sought to give developing nations more control over their economic resources and improve their bargaining power in the global economy.

Answer is Asians because rice was known to them first

Primary Focus of the IMF and the World Bank
The International Monetary Fund (IMF) and the World Bank were established in 1944 during the Bretton Woods Conference, primarily aimed at addressing the economic challenges following World War II.
IMF's Focus
- The IMF was created to ensure the stability of the international monetary system.
- Its primary role was to provide financial assistance to countries facing balance of payments problems, particularly industrial nations recovering from the war.
- By offering short-term loans and policy advice, the IMF aimed to stabilize currencies and promote international economic cooperation.
World Bank's Focus
- The World Bank, on the other hand, was established to support long-term economic development and reduce poverty, especially in developing nations.
- Its initial focus was on funding infrastructure projects in industrial countries that were essential for rebuilding their economies post-war.
- By providing capital for projects such as roads, schools, and hospitals, the World Bank aimed to stimulate economic growth in these countries.
Conclusion
- While both institutions later expanded their roles to include poverty alleviation and support for developing countries, their initial focus was indeed on meeting the financial needs of industrial countries.
- This historical context is crucial to understanding their evolving missions and the global economic landscape today.

The Bretton Woods system established fixed exchange rates where currencies were pegged to the US dollar, and the dollar was pegged to gold.