10 most difficult water riddles A list of ten (out of 20) water related questions that are the most often answered incorrectly Water quiz 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 25% 1.01.019%7.07.050%10.010.05%It depends on the temperatureIt depends on the temperature25%Created by: globalquiz.org. Statistics based on 4042 answers in 4 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 30% North-west ScotlandNorth-west Scotland10%Central Amazon BasinCentral Amazon Basin51%Tuvalu IslandsTuvalu Islands8%Southern foothills of the HimalayasSouthern foothills of the Himalayas30%Created by: KYRTAPS. Statistics based on 5364 answers in 2 languages »meteorology 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 34% Lake BailkalLake Bailkal23%Lake SuperiorLake Superior34%Great Bear LakeGreat Bear Lake23%Lake OnegaLake Onega18%Created by: globalquiz.org. Statistics based on 7665 answers in 2 languages »ice 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 35% between Finland and Russiabetween Finland and Russia31%between Sweden and Finlandbetween Sweden and Finland35%between Sweden and Denmarkbetween Sweden and Denmark16%between Finland and Estoniabetween Finland and Estonia15%Created by: globalquiz.org. Statistics based on 10347 answers in 2 languages »Baltic Sea 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 6642 answers in 4 languages »Antarctic 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 temperature34%sea currents speedsea currents speed13%water salinitywater salinity38%sea depthsea depth13%Created by: globalquiz.org. Statistics based on 12060 answers in 4 languages »satellite photography riddles » How old is Baltic Sea?12 000 years old. Baltic Sea is one of the youngest seas in the world. It was formed after the last ice age as ice-lake, which later turned into a sea.hard 41% 1200 years old1200 years old5%12 000 years old12 000 years old41%120 000 years old120 000 years old32%12 000 000 years old12 000 000 years old21%Created by: KYRTAPS. Statistics based on 11416 answers in 4 languages »geology riddles » What is the name of the line on the map which joins points of equal rainfall?Isyhyet joins points where the amount of precipitation (rainfall, snow etc) is the same. hard 43% IsohigraIsohigra8%IsohydraIsohydra37%IydroizohipsaIydroizohipsa10%IsyhyetIsyhyet43%Created by: Paweł Kołodziejczyk. Statistics based on 9161 answers in 2 languages »maps riddles » Which water phase is the most dense?Liquid water. Ice frozen at atmospheric pressure is approximately 8.3% less dense than liquid water. Thus, ice floats on liquid water.hard 49% liquid waterliquid water49%water icewater ice34%water vaporwater vapor4%all have the same densityall have the same density11%Created by: Kasia. Statistics based on 18927 answers in 2 languages »physics riddles » How is the soilless cultivation of plants called?Hydroponics is a subset of hydroculture and is a method of growing plants using mineral nutrient solutions, in water, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite or gravel.hard 51% hydrologyhydrology9%hydroculturehydroculture19%hydroponicshydroponics51%hydrofarminghydrofarming20%Created by: Paweł Kołodziejczyk. Statistics based on 13565 answers in 2 languages »fruits riddles » Play water quiz and see all the questions.