2000g radio activ isotope have 10 day T1/2. So 40 days have a four T1/2 answer is 2000g.
Description : A radioisotope has a half life of 10 days. If today there is `125 g ` of it left, what was its mass 40 days earlier ? a)600g b)1000g c)1250g d)2000g
Last Answer : A radioisotope has a half life of 10 days. If today there is `125 g ` of it left, what was its mass ... d)2000g A. 600g B. 1000g C. 1250g D. 2000g
Description : The half life of radioactive isotope is 3 hour. If the initial mass of isotope were 256 g, the mass of it remaining undecayed after 18 hr is a)12 g b)
Last Answer : The half life of radioactive isotope is 3 hour. If the initial mass of isotope were 256 g, the mass of it remaining ... 4 g B. 8 g C. 12 g D. 16 g
Description : A radioactive isotope having a half life of 3 days was received after 12 days. It was found that there were 3 gm of the isotopes in the container. The
Last Answer : A radioactive isotope having a half life of 3 days was received after 12 days. It was found that there were 3 gm of ... 48 g B. 36 g C. 24 g D. 12 g
Description : Assertion (A) : Half life of a radioactive isotope is the time required to decrease its mass number by half Reason (R ) : Half life of radioactive iso
Last Answer : Assertion (A) : Half life of a radioactive isotope is the time required to decrease its mass number by half ... . If both (A) and (R ) are incorrect.
Description : The time required for half of the __________ of a radioactive isotope to decay is called its half life. (A) Nuclei (B) Electrons
Last Answer : (A) Nuclei
Description : Pick out the wrong statement. (A) α-particle emission from a radioactive element makes it electrically negative (B) β-particle emission from a radioactive element makes it electrically ... ) The disintegration constant of a radioactive isotope is independent of pressure, temperature or concentration
Last Answer : (C) A radioactive element having a half life period of 20 years will completely disintegrated in 40 years
Description : Initial amount of the radioactive element with half life 10 days is 16 g. What amount in gm of this element will remain after 40 days?
Last Answer : Initial amount of the radioactive element with half life 10 days is 16 g. What amount in gm of this element will remain after 40 days?
Description : The amount of a radioactive material (having a half life of 100 years) remaining after 400 years will be __________ of its original weight. (A) 1/2 (B) 1/4 (C) 1/8 (D) 1/16
Last Answer : (D) 1/16
Description : The time taken for a radioactive element to reduce to 50% of its original weight is __________ years, if its half life period is 12 years. (A) 24 (B) 18 (C) 6 (D) 36
Last Answer : (B) 18
Description : What name is given to the time taken for half the atoms in a sample of a radioactive isotope to decay?
Last Answer : Half-life
Description : What fraction of an original sample of a radio isotope remains after 3 half-life periods?
Last Answer : One eighth remains.
Description : If 4 gm of a radioisotope has a half life period of 10 days, the half life of 2 gm of the same isotope will be __________ days. (A) 5 (B) 10 (C) 20 (D) 30
Last Answer : (B) 10
Description : The half-life of an isotope of an element is 5 days. The mass of a 10 gram sample of this isotope remaining after 20 days is: w) 0.312 grams x) 0.625 grams y) 1.25 grams z) 2.50 grams
Last Answer : ANSWER: X -- 0.625 GRAMS
Description : The activity of a radioactive element reduces to `(1//16)th` of its original value in 30 years. Find its half life?
Last Answer : The activity of a radioactive element reduces to `(1//16)th` of its original value in 30 years. Find its half ... B. 75 trs C. 7.5 day D. 75 month
Description : The half life of a radioactive element is 8-days. How long it take to reduce it from 10 mg to 5 mg? A. 4 days B. 12 days C. 16 days D. 8 days (Answer) E. None of these
Last Answer : D. 8 days (Answer)
Description : The radioactive isotope of hydrogen is called--------- and its nucleus contains --------proton and --- --neutron.
Last Answer : Ans: Tritium, one and two
Description : If you start with 24 grams of a radioactive element with a half-life of one month, how many grams of the radioactive element will be left after 2 months? w) 1.5 grams x) 3 grams y) 6 grams z) 12 grams
Last Answer : ANSWER: Y -- 6 GRAMS
Description : Is the decay of a radioactive isotope predictable (causally determined) or not?
Last Answer : At this point it seems to be a result of quantum indeterminacy. In other words, since the Heisenberg uncertainty principle is in effect at that level, all we can determine is probability (hence a predictable ... , it is deterministic and we will (hopefully) one day be able to understand it as such.
Description : The radioactive isotope of cerium - 137 of weigh 8g was collected on 1st Feb. 2006 kept in a sealed tube. On 1st July, 2006, it was found that only 0.
Last Answer : The radioactive isotope of cerium - 137 of weigh 8g was collected on 1st Feb. 2006 kept in a sealed tube. On ... days B. 30 days C. 25 days D. 50 days
Description : (A) The archaeological studies are based on the radioactive decay of carbon-14 isotope. (R ) The ratio of C-14 to C-12 in the animals of plants is the
Last Answer : (A) The archaeological studies are based on the radioactive decay of carbon-14 isotope. (R ) The ratio of C ... D. If both (A) and (R ) are incorrect.
Description : Which radioactive isotope is used to detect tumours?
Last Answer : Which radioactive isotope is used to detect tumours? A. `.^(74)As` B. `.^(24)Na` C. `.^(131)I` D. `.^(60)Co`
Description : When `._(13)^(27)Al` is bombarded whith `alpha`-particles, a radioactive isotope of phosphorus `._(15)^(30)P` with the emission of …. Is formed
Last Answer : When `._(13)^(27)Al` is bombarded whith `alpha`-particles, a radioactive isotope of phosphorus ` ... A. neutrons B. protons C. positrons D. electrons
Description : When an isotope is blank it is radioactive?
Last Answer : When an isotope is unstable, it is said to be radioactive.
Description : When does an isotope undergo radioactive decay?
Last Answer : An atom of a given isotope will undergo radioactive decay whenever it feels like it. No joke. The nucleus of a radioactive isotope is unstable. Always. But that atom has no predictable moment ... to decay, except that those with very short half lives will pretty much disappear relatively quickly.
Description : What type of decay involves only the release of high-energy photons and therefore does not change the mass of an atom of a radioactive isotope?
Last Answer : High-energy photons are gamma rays; the decay is called gamma decay. Please note that the mass of an atom DOES change, since a loss of energy is accompanied by a loss in mass.
Description : A radioactive isotope labeled cDNA probe is used in (A) Southern blotting (B) Northern blotting (C) Both (A) and (B) (D) None of these
Last Answer : Answer : C
Description : Which one is the radioactive isotope of hydrogen? (A) Deuterium (B) Ortho-hydrogen (C) Tritium (D) None of these
Last Answer : (C) Tritium
Description : A radioactive isotope undergoes decay with respect to time following __________ law. (A) Logarithmic (B) Exponential (C) Linear (D) Inverse square
Last Answer : (B) Exponential
Description : Radioactive isotope of Uranium used in Nuclear Bomb is ? A.92 U 235 (Answer) B.92 U 234 C. 92 U 233 D. 92 U 238
Last Answer : A.92 U 235 (Answer)
Description : Which technique has helped in investigation of Calvin cycle? (a) X-ray crystallography (b) X-ray technique (c) Radioactive isotope technique (d) Intermittent light
Last Answer : (c) Radioactive isotope technique
Description : If a radioactive sample has decayed until only one eighth of the original sample remains unchanged how many half-lives have elapsed?
Last Answer : 3
Description : A radioactive element gets spilled over the floor of a room. Its half life period is 30 days. If its initial activity is ten times the permissible val
Last Answer : A radioactive element gets spilled over the floor of a room. Its half life period is 30 days. If its initial ... B. 1000 days C. 300 days D. 10 days
Description : The half life period of a radioactive element is 100 days. After 400 days, one gm of the element will be reduced to __________ gm. (A) 1/4 (B) 1/8 (C) 1/2 (D) 1/16
Description : The physical half life of radioactive 131I is: A. 8 hours B. 8 days C. 16 days D. 60 day
Last Answer : . 8 days
Description : A cylinder contains oxygen at a pressure of 10 atm and a temperature of 300 K. The volume of the cylinder is 10 liters. What is the mass of the oxygen in grams? Molecular weight (MW) of oxygen is 32 g/mole? a. 125.02 b. 130.08 c. 135.05 d. 120.04
Last Answer : 130.08 {(10atm)(10)(32)/(0.0821) (300K)}
Description : If the half-life of a radioisotope is 2 days, after how many days is the quantity reduced to 12.5% of its original amount? w) 4 days x) 6 days y) 8 days z) 10 days
Last Answer : ANSWER: X -- 6 DAYS
Description : Consider the following decay series: `A to B to C to D` Where, A,B and C are radioactive elements with half lives of 4,5 sec, 15 days and 1 sec respec
Last Answer : Consider the following decay series: `A to B to C to D` Where, A,B and C are radioactive elements with half ... mol of C, 1/4 mol of D and noen of A
Description : A radioactive element `X`, decays by the sequence and with half-lives, given below, `X underset(30"min")overset(alpha)(rarr) Y underset(2"days")overse
Last Answer : A radioactive element `X`, decays by the sequence and with half-lives, given below, `X underset(30"min" ... D. The mass number of Y is greater than X
Description : What is the half-life of carbon 12 isotope ?
Last Answer : Carbon -12 is a normal atom. It is not radioactive. C- 14 is radioactive. Its half -life is 5,630 years
Description : The `.^(60)C` isotope decays with a half life of 5.3 years. How long would it take for 7/8 of a sample of 500 mg of `.^(60)Co` to disintegrate?
Last Answer : The `.^(60)C` isotope decays with a half life of 5.3 years. How long would it take for 7/8 of a sample ... B. 15.9 years C. 10.6 years D. 5.3 years
Description : Fifty micrograms of an isotope have decayed to 12.5 micrograms after 12 hours. What is the half life of the radioisotope?
Last Answer : ANSWER: SIX HOURS
Description : For determine the specific gravity of soil solids, using a pycnometer of 500 cc., the following data is available : Weight of dry empty pycnometer = 125 g Weight of dried soil and pycnometer = 500 g Weight of dried soil and distilled ... of soil solids, is (A) 2.0 (B) 2.25 (C) 2.50 (D) 2.75
Last Answer : (C) 2.50
Description : At radioactive equilibrium, the ratio between two atoms of radioactive elements `A` and `B` is `3.1 xx 10^(9) : 1`. If the half-life period of `A` is
Last Answer : At radioactive equilibrium, the ratio between two atoms of radioactive elements `A` and `B` is `3.1 xx 10^(9) ... B. 3 yrs C. 3.3 yrs D. None of these
Last Answer : At radioactive equilibrium, the ratio between two atoms of radioactive elements `A` and `B` is `3.1 xx 10^(9) : ... . 4.65 yrs C. 5.46 yrs D. 5.64 yrs
Description : The amount of a radioisotope remaining undecayed after a time equal to four times its half life, will be __________ percent. (A) 3.125 (B) 6.25 (C) 12.50 (D) 25
Last Answer : (B) 6.25
Description : The `t_(1//2)` of a radionuclide is 8 hours. Starting with 40 g of the isotope, the amount in gm remainig after one day will be:
Last Answer : The `t_(1//2)` of a radionuclide is 8 hours. Starting with 40 g of the isotope, the amount in gm remainig after one day will be:
Description : What is the half life of Iodine-125?
Last Answer : About 60 days.
Description : What is the half life of 3 g sample of radioisotope that decay to 0.75 g in 30 days?
Last Answer : 15 days
Description : The half life of Ig G is (A) 2–8 days (B) 1–4 days (C) 19–24 days (D) 6 days