This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

[Q]: Passage: Zinc metal is produced using extractive metallurgy. After grinding the ore, froth flotation, which selectively separates minerals from gangue by taking advantage of differences in their hydrophobicity, is used to get an ore concentrate. This concentrate consists of about 50% zinc with the rest being sulfur (32%), iron (13%), and SiO
2 (5%). The composition of this is normally zinc sulfide (80% to 85%), iron sulfide (7.0% to 12%), lead sulfide (3.0% to 5.0%) silica (2.5% to 3.5%), and cadmium sulfide (0.35% to 0.41%).
[A]: What is used to eliminate the metal zinc?


[Q]: Passage: Modern philosophical materialists extend the definition of other scientifically observable entities such as energy, forces, and the curvature of space. However philosophers such as Mary Midgley suggest that the concept of "matter" is elusive and poorly defined.
[A]: Why does Mary Midgley suggest matter is well defined? 


[Q]: Passage: In 1821, after Mexico's War of Independence from Spain, Texas was part of the United Mexican States as the state of Coahuila y Tejas. A large influx of Americans soon followed, originally with the approval of Mexico's president. In 1836, the now largely "American" Texans, fought a war of independence from the central government of Mexico and established the Republic of Texas. In 1846, the Republic dissolved when Texas entered the United States of America as a state. Per the 1850 U.S. census, fewer than 16,000 Texans were of Mexican descent, and nearly all were Spanish-speaking people (both Mexicans and non-Spanish European settlers who include German Texan) who were outnumbered (six-to-one) by English-speaking settlers (both Americans and other immigrant Europeans).[citation needed]
[A]:
What was the name for the area Coahuila y Tejas was part of?