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 25% the OH − ion concentration is smaller than the H+ ion concentrationthe OH − ion concentration is smaller than the H+ ion concentration478the OH − ion concentration is greater than the H+ ion concentrationthe OH − ion concentration is greater than the H+ ion concentration365the OH − ion concentration is equal of the H+ ion concentrationthe OH − ion concentration is equal of the H+ ion concentration535Such solution doesn't existSuch solution doesn't exist526 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% 0-3600-36024790-18090-18048610-900-90164180-360180-3601041 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 cm314164/3π cm34/3π cm340554,3π cm34,3π cm3733It isn't possible to calculateIt isn't possible to calculate834 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% 4410888881665800Not enough dataNot enough data172 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% 1/31/351920,30,343333%33%979Both answers 1/3 and 33% are correctBoth answers 1/3 and 33% are correct3262 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 Einstein3981Blaise PascalBlaise Pascal1440Isaac NewtonIsaac Newton1448all of the aboveall of the above1430 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% 238829902388299096416769023167690237118383772963837729691011723835117238351712 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 51% 9999994481000100059899999999321010000100004431 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 meters5976by approx 6 kilometersby approx 6 kilometers2377by approx 60 kilometersby approx 60 kilometers2926by approx 6000 kilometersby approx 6000 kilometers2350 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% oneone7926twotwo1977threethree505fourfour414 Play mathematics quiz and see all the questions.