10 most difficult water riddles A list of ten (out of 27) water related questions that are the most often answered incorrectly Water quiz What does synthesis gas (water gas) consist of?Carbon monoxide (CO) and hydrogen (H2). Water gas is a mixture of carbon monoxide and hydrogen produced from synthesis gas. Synthesis gas is a useful product, but requires careful handling due to its flammability and the risk of carbon monoxide poisoning. The water-gas shift reaction can be used to reduce the carbon monoxide while producing additional hydrogen, resulting in water gas. very hard 21% oxygen (O2) and hydrogen (H2)oxygen (O2) and hydrogen (H2)21%methane (CH4) and water (H2O)methane (CH4) and water (H2O)32%carbon dioxide (CO2) and hydrogen (H2)carbon dioxide (CO2) and hydrogen (H2)24%carbon monoxide (CO) and hydrogen (H2)carbon monoxide (CO) and hydrogen (H2)21%Created by: Tschuka. Statistics based on 3109 answers in 3 languages »alcohol riddles » What is exactly the pH value of distilled water?It depends on the temperature. Pure water is about 7 at 25 °C; this value decreases with increasing temperatures. At 50 °C, it is 6.55. It is also worth to note, that water that has been exposed to air is mildly acidic, because it absorbs carbon dioxide from the air.very hard 24% 1.01.018%7.07.051%10.010.05%It depends on the temperatureIt depends on the temperature24%Created by: globalquiz.org. Statistics based on 4862 answers in 5 languages »acids riddles » Which place in the world has the highest average annual precipitation? Southern foothills of the Himalayas. Mawsynram village in northeast India has the highest average annual total percipitation in the world (11,872 mm = 467.4 in). There, hot and moist air from south of India approaches Himalayas. It rises up, cools and loses water.very hard 29% North-west ScotlandNorth-west Scotland10%Central Amazon BasinCentral Amazon Basin52%Tuvalu IslandsTuvalu Islands8%Southern foothills of the HimalayasSouthern foothills of the Himalayas29%Created by: KYRTAPS. Statistics based on 6618 answers in 2 languages »meteorology riddles » At what temperature does the water have the highest density?4°C (39.2°F). Increasing the temperature generally decreases the density, but water is a notable exception: the density of water increases between its melting point at 0 °C and 4 °C. Similar behavior is observed in silicon at low temperatures.very hard 29% 0°C (32°F)0°C (32°F)33%100°C (212°F)100°C (212°F)16%-273°C (-459.4°F)-273°C (-459.4°F)19%4°C (39.2°F)4°C (39.2°F)29%Created by: Tschuka. Statistics based on 4554 answers in 2 languages »numbers riddles » What ions are formed during self-ionization of water?H₃O + and OH-. The self-ionization of water is an ionization reaction in pure water or in an aqueous solution, in which a water molecule, H2O, deprotonates to become a hydroxide ion, OH−. The hydrogen nucleus, H+, immediately protonates another water molecule to form hydronium, H3O+. It is an example of autoprotolysis, and exemplifies the amphoteric nature of water. very hard 31% H₃O + and OH-H₃O + and OH-31%HO₂- and H₂OHO₂- and H₂O18%OH + and H₃O-OH + and H₃O-15%All answers are correctAll answers are correct33%Created by: Tschuka. Statistics based on 762 answers in 2 languages »physics riddles » Where is the saltiest lake in the world?In Antarctica. With a salinity level of over 40%, Don Juan Pond is the saltiest of the Antarctic lakes. This salinity allows the pond to remain liquid even at temperatures as low as −50 °C (−58 °F) due to the interference of salts with the bonding of water molecules. Don Juan Pond was discovered in 1961 by George H. Meyer.very hard 33% in Antarcticain Antarctica33%In AustraliaIn Australia6%in Israelin Israel43%in Turkmenistanin Turkmenistan16%Created by: Tschuka. Statistics based on 1415 answers in 3 languages »salt riddles » What sound can be heard when approaching an iceberg?A fizz. When a piece of iceberg ice melts, it makes a fizzing sound called "Bergie Seltzer". This sound is made when the water-ice interface reaches compressed air bubbles trapped in the ice. As this happens, each bubble bursts, making a 'popping' sound. The bubbles contain air trapped in snow layers very early in the history of the ice, that eventually got buried to a given depth (up to several kilometers) and pressurized as it transformed into firn then to glacial ice.very hard 35% a cracking noisea cracking noise46%a fizza fizz35%a roara roar7%a whispera whisper10%Created by: globalquiz.org. Statistics based on 9705 answers in 5 languages »ice riddles » On which of the following lakes are icebreakers most extensively used?Lake Superior. The Great Lakes are important shipping route, mainly for bulk goods like iron ore or coal. Several icebreakers are busy each winter to keep the route open.very hard 36% Lake BailkalLake Bailkal22%Lake SuperiorLake Superior36%Great Bear LakeGreat Bear Lake23%Lake OnegaLake Onega17%Created by: globalquiz.org. Statistics based on 11042 answers in 2 languages »lakes riddles » Where is the Gulf of Bothnia?Between Sweden and Finland. A number of rivers from both countries flow into the gulf. As a result, a salinity gradient exists from north to south. In the south the water is the normal brackish water of the Baltic Sea, but in the north, the salinity is so low, that one can no longer taste the salt in the water and many freshwater fish thrive in it.very hard 36% between Finland and Russiabetween Finland and Russia31%between Sweden and Finlandbetween Sweden and Finland36%between Sweden and Denmarkbetween Sweden and Denmark16%between Finland and Estoniabetween Finland and Estonia15%Created by: globalquiz.org. Statistics based on 12848 answers in 3 languages »Baltic Sea riddles » What does the color range represent in this picture?Water salinity. Launched June 10, 2011, Aquarius is NASA’s first satellite instrument specifically designed to study the salt content of ocean surface waters. The complete first year dataset of NASA's Aquarius instrument reveals seasonal changes in the Amazon River's plume. Depending on the prevailing currents, the river's freshwater outflow heads east toward Africa or bends up north to the Caribbean.very hard 38% water temperaturewater temperature33%sea currents speedsea currents speed13%water salinitywater salinity38%sea depthsea depth14%Created by: globalquiz.org. Statistics based on 15891 answers in 4 languages »satellite photography riddles » Play water quiz and see all the questions.