Problem: Apart from its use as a reactant, H
2 has wide applications in physics and engineering. It is used as a shielding gas in welding methods such as atomic hydrogen welding. H2 is used as the rotor coolant in electrical generators at power stations, because it has the highest thermal conductivity of any gas. Liquid H2 is used in cryogenic research, including superconductivity studies. Because H
2 is lighter than air, having a little more than 114 of the density of air, it was once widely used as a lifting gas in balloons and airships.
Where else is H2 applied?
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Answer: in physics and engineering

Problem: The Juscelino Kubitschek bridge, also known as the 'President JK Bridge' or the 'JK Bridge', crosses Lake Paranoa in Brasilia. It is named after Juscelino Kubitschek de Oliveira, former president of Brazil. It was designed by architect Alexandre Chan and structural engineer Mario Vila Verde. Chan won the Gustav Lindenthal Medal for this project at the 2003 International Bridge Conference in Pittsburgh due to "...outstanding achievement demonstrating harmony with the environment, aesthetic merit and successful community participation".
What does the Mario Vila Verde bridge cross?
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Answer: unanswerable

Problem: In 1952 researchers at Ciba discovered the first orally available vasodilator, hydralazine. A major shortcoming of hydralazine monotherapy was that it lost its effectiveness over time (tachyphylaxis). In the mid-1950s Karl H. Beyer, James M. Sprague, John E. Baer, and Frederick C. Novello of Merck and Co. discovered and developed chlorothiazide, which remains the most widely used antihypertensive drug today. This development was associated with a substantial decline in the mortality rate among people with hypertension. The inventors were recognized by a Public Health Lasker Award in 1975 for "the saving of untold thousands of lives and the alleviation of the suffering of millions of victims of hypertension".
Chlorothiazide helped reduce the mortality rate among those with what disease?
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Answer:
hypertension