Mathematics questions This is a list of recently added questions about mathematics. Play mathematics quiz and see all the questions. Which of the following is true for the solution with the pH=0?The OH − ion concentration is smaller than the H+ ion concentration. In chemistry, pH is a numeric scale used to specify the acidity or alkalinity of an aqueous solution. It is the negative of the logarithm to base 10 of the activity of the hydrogen ion .Traditionally the pH is being defined as: pH = - log10 [H+], where [H+] it is a H+ ions concentration in mol/dm^3 (M). So if pH = 0 this H+ ions concentration is 1 mol/dm^3 and the solution is strongly acidic.Created by: Paweł Kołodziejczyknumbers riddles »very hard 24% the OH − ion concentration is smaller than the H+ ion concentrationthe OH − ion concentration is smaller than the H+ ion concentration430the OH − ion concentration is greater than the H+ ion concentrationthe OH − ion concentration is greater than the H+ ion concentration339the OH − ion concentration is equal of the H+ ion concentrationthe OH − ion concentration is equal of the H+ ion concentration493Such solution doesn't existSuch solution doesn't exist482 How many degrees an obtuse angle can have ?90-180. The obtuse angle may measure from 90 to 180 degrees. Angles having a degree of 0 to 90 are acute angles, whereas those from 180 to 360 - concave angles.Created by: TotalBellendgeometry riddles »easy 76% 0-3600-36022490-18090-18043640-900-90153180-360180-360944 What is the volume of a soap bubble with radius R=1 cm?4/3π cm3. Equation for the volume of a sphere: 4/3πR^3.Created by: Paweł Kołodziejczyknumbers riddles »hard 57% 3/4π cm33/4π cm312734/3π cm34/3π cm335724,3π cm34,3π cm3666It isn't possible to calculateIt isn't possible to calculate740 What is the result of 2+2*2?6. The multiplication has a priority over addition, and so the result is 2+(2*2) = 2+4 = 6.Created by: Paweł Kołodziejczyknumbers riddles »very easy 83% 448988791665201Not enough dataNot enough data155 Which of the following numbers is the greatest?1/3. Quite surprisingly, most players answer that both answers 1/3 and 33% are correct. But 1/3 is more than 33%. (it is 33.3333333...)Created by: globalquiz.orgnumbers riddles »hard 52% 1/31/347600,30,339933%33%903Both answers 1/3 and 33% are correctBoth answers 1/3 and 33% are correct3063 Which famous scientist was born on the Pi day? (March 14)Albert Einstein. 14 of March is celebrated on many schools and universities as both Pi Day and the birthday of Albert Einstein. On of the traditions is the 'Pi Pie' (pictured).Created by: globalquiz.orgscientists riddles »hard 47% Albert EinsteinAlbert Einstein3719Blaise PascalBlaise Pascal1347Isaac NewtonIsaac Newton1371all of the aboveall of the above1345 Which of the following is a prime number?16769023. A prime number has no positive divisors other than 1 and itself. Hence, a prime bigger than 2 cannot be even. All prime numbers bigger than 5, written in the usual decimal system, end in 1, 3, 7, or 9. Created by: Sumit Tamangmath riddles »average 66% 238829902388299092516769023167690236654383772963837729685111723835117238351626 How many possible code combinations are there for this kind of lock?10000. The possible codes are from 0000 to 9999 inclusive.Created by: Teddybicycles riddles »hard 50% 9999994221000100056799999999301110000100004128 If Earth's radius was larger by 1 meter, how much longer would its equator be?By approx 6 meters. For each circle, the length of the circumference is c=2πr. Hence, if a radius grows by 1 meter, the circumference grows by 2 π meters - no matter what the initial value of radius was.Created by: SpikeMeEarth riddles »hard 43% by approx 6 metersby approx 6 meters5412by approx 6 kilometersby approx 6 kilometers2198by approx 60 kilometersby approx 60 kilometers2725by approx 6000 kilometersby approx 6000 kilometers2178 How many edges does a Möbius strip have?One. The Möbius strip is a surface with only one side and only one boundary component (edge). A line drawn starting from the seam down the middle will meet back at the seam but at the "other side". If continued the line will meet the starting point and will be double the length of the original strip.Created by: globalquiz.orggeometry riddles »easy 73% oneone7488twotwo1874threethree479fourfour388 Play mathematics quiz and see all the questions.