Which organisation officially launched the International Year of the Periodic Table of Chemical Elements in 2019?

Introduction / Context:
The year 2019 was proclaimed the International Year of the Periodic Table of Chemical Elements to celebrate the 150th anniversary of Dmitri Mendeleev's work on the periodic system. The official launch of this special year was done by a United Nations related organisation that focuses on education, science and culture. This question checks whether you can correctly connect that scientific celebration with the right institution.

Given Data / Assumptions:

• The question asks which organisation officially launched the International Year of the Periodic Table of Chemical Elements.
• Options: UNESCO, UNO, WHO and FHO.
• The International Year is related to science and education at a global level.

Concept / Approach:
UNESCO, the United Nations Educational, Scientific and Cultural Organization, is the primary specialised agency that deals with international cooperation in science and education. It hosted the formal launch of the International Year of the Periodic Table at its headquarters in Paris in January 2019. While the wider UN system supported the year, UNESCO was the specific organisation that took the lead and organised the opening ceremony.

Step-by-Step Solution:
Step 1: Recognise that the periodic table is a scientific topic closely tied to chemistry and education. Step 2: Recall that UNESCO works directly in the fields of education, science and culture, making it a natural organiser for such a celebration. Step 3: Note that UNO is a general term for the overall United Nations, while WHO focuses on health, and FHO is not a standard, widely recognised UN agency acronym. Step 4: Link the 2019 International Year of the Periodic Table with UNESCO's scientific and educational mission. Step 5: Select UNESCO as the correct answer.

Verification / Alternative check:
Reports on the International Year of the Periodic Table describe how the official launch ceremony took place at UNESCO headquarters in Paris and emphasise UNESCO's role in coordinating events and partnerships. This confirms that UNESCO, acting as the UN's science and education arm, was the organisation that formally launched the year.

Why Other Options Are Wrong:
United Nations Organization (UNO): This is a general reference to the UN system. While the UN as a whole supported the International Year, the specific launch and coordination were carried out by UNESCO.
World Health Organization (WHO): WHO is primarily concerned with global health issues and was not the main organiser of this scientific commemoration.
Food and Health Organization (FHO): This is not a standard name for a UN agency and appears incorrect in this context.

Common Pitfalls:
Some candidates may choose UNO because they see "International Year" and think directly of the overall United Nations. However, many International Years are implemented through a particular specialised agency that fits the subject. To avoid this mistake, associate scientific and educational celebrations such as the periodic table anniversary with UNESCO, not with WHO or vague names like FHO.

Final Answer:
The International Year of the Periodic Table of Chemical Elements was officially launched by UNESCO.