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
Description : Two radioactive elements X and Y have half lives 6 min and 15 min respectively. An experiment starts with 8 times as many atoms of X as Y. how long it
Last Answer : Two radioactive elements X and Y have half lives 6 min and 15 min respectively. An experiment starts with 8 times ... B. 12 min C. 48 min D. 30 min
Description : The half - life of a radioactive substance depends upon (a) Its temperature (b) The external pressure (c) The mass of the substance (d) The strength of the nuclear force between the nucleons its atoms
Last Answer : Ans:(d)
Description : `3.011 xx 10^(22)` atoms of an element weight 1.15 g. The atomic mass of the element is :-
Last Answer : `3.011 xx 10^(22)` atoms of an element weight 1.15 g. The atomic mass of the element is :- A. 10 amu B. 2.3 amu C. 35.5 amu D. 23 amu
Description : A reaction develop nuclear energy at the rate of `3 xx 10^(4) kW`. How many atoms of `.^(215)U` undergo fission per second? How much `.^(235)U` is bur
Last Answer : A reaction develop nuclear energy at the rate of `3 xx 10^(4) kW`. How many atoms of `.^(215)U` ... constant is `6.023 xx 10^(26)` per kg mole)
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 : The half life period of a radioactive substance is best determined by counting the number of alpha particles emitted per second in a GeigerMuller counter from its known quantity. If the half life period of a ... in four months (D) 1/8th of it will remain intact at the end of four months
Last Answer : (B) It will completely disintegrate in two months
Description : If `3//4` quantity of a radioactive substance disintegrates in 2 hours, its half`-` life period will be a)`15 mi n` b) `30 mi n` c)`60 mi n` d)`90 mi
Last Answer : If `3//4` quantity of a radioactive substance disintegrates in 2 hours, its half`-` life period will be ... B. 45 minutes C. 30 minutes D. 15 minutes
Last Answer : If `3//4` quantity of a radioactive substance disintegrates in 2 hours, its half`-` life period will be a)`15 mi n ... mi n` c)`60 mi n` d)`90 mi n`
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
Last Answer : If `3//4` quantity of a radioactive substance disintegrates in 2 hours, its half`-` life period will be ... B. 30 minutes C. 60 minutes D. 90 minutes
Description : What is the average life of a radioactive atom having a 'half life period' of T? (A) 1.44 T (B) 0.144 T (C) 14.4 T (D) 2T
Last Answer : (A) 1.44 T
Description : 75% of a radioactive element decays in 6 hours. Its half life period is __________ hours. (A) 3/4 (B) 1/6 (C) 3 (D) 4
Last Answer : (C) 3
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 : The half life period of a radioactive element depends on its (A) Temperature (B) Pressure (C) Amount (D) None of these
Last Answer : (D) None of these
Description : . The half life period of a radioactive element depends upon the (A) Temperature (B) Pressure (C) Amount of element present (D) None of these
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
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 : 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 : In a spent fuel assembly, the radioactive elements having the longest half-lives are the: w) fission products x) actinides y) activation products z) radioisotopes of lead
Last Answer : ANSWER: X -- ACTINIDES
Description : If A and B two sets containing 2 elements and 4 elements, respectively. Then, the number of subsets of `A xx B` having 3 or more elements, is
Last Answer : If A and B two sets containing 2 elements and 4 elements, respectively. Then, the number of subsets of `A xx B` ... `256` B. `220` C. `219` D. `211`
Description : Cri-du-chat syndrome in humans is caused by the (a) trisomy of 21st chromosome (b) fertilisation of an XX egg by a normal Y-bearing sperm (c) loss of half of the short arm of chromosome 5 (d) loss of half of the long arm of chromosome 5.
Last Answer : (c) loss of half of the short arm of chromosome 5
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 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 : A radioactive isotope has a half-life of 10 days. If today there are 125 g of it left, what was its original weight 40 days earlier (a) 600 g (b) 1000 g (c) 1250 g (d) 2000 g
Last Answer : Half life = 10days The formula which is, 1/(2)^n × original weight = Weight left today. To obtain the value of n = divide no of days by half life ie.,n= 40/10= 4 n=4 So, 1/(2)^n × original Weight = 125g 1/(2)^4 × Original weight = 125 Original weight = 16×125 = 2000g
Description : The value of `((log_(2)9)^(2))^((1)/(log_(2)(log_(2)9)))xx(sqrt(7))^((1)/(log_(4)7))` is .......... .
Last Answer : The value of `((log_(2)9)^(2))^((1)/(log_(2)(log_(2)9)))xx(sqrt(7))^((1)/(log_(4)7))` is .......... .
Description : (a) What are groups' and periods' in the periodic table'? (b) Two elements M and N belong to group I and II respectively and are in the same period of the periodic ... Sizes of their atoms Their metallic characters Their valencies in forming oxides Molecular formulae of their chlorides -Science
Last Answer : (a) The vertical columns in the periodic table are called groups'. The horizontal rows in the periodic table are called periods'. (b) M' and N' belong to same period but group I ... oxides. Valency goes on increasing first and then decreases. MCI, NCI2 are molecular formulae of their chlorides.
Description : If the amount of radioactive substance is increased three times, the number of atoms disintegrated per ubit time would :
Last Answer : If the amount of radioactive substance is increased three times, the number of atoms disintegrated per ubit ... 3)` rd of the original number of atoms
Description : Can the decay half-life of a radioactive material be changed? -Physics
Last Answer : Yes, the decay half-life of a radioactive material can be changed. Radioactive decay happens when an unstable atomic nucleus spontaneously changes to a lower-energy state and spits out a bit of ... radiometric dating are so accurate because decay half-lives in nature are so close to constant.
Description : What is the half-life of a radioactive element ?
Last Answer : Half-life is the amount of time during which half of the nucleus of an element is irradiated.
Description : A frheshly prepared radioactive source of half life 2 hrs emits radiation of intensity which is 32 times the permissible safe value of intensity. Whic
Last Answer : A frheshly prepared radioactive source of half life 2 hrs emits radiation of intensity which is 32 times the ... B. 5hrs C. 10 hrs D. 32 hrs
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 : Radioactive decay follows first-order kinetic. The mean life and half-life of nuclear decay process are `tau = 1// lambda` and `t_(1//2) = 0.693//lamb
Last Answer : Radioactive decay follows first-order kinetic. The mean life and half-life of nuclear decay process are `tau = 1// ... `tau = (t_(1//2))/(0.693)`
Last Answer : Radioactive decay follows first-order kinetic. The mean life and half-life of nuclear decay process ... on the amount of element not yet decayed
Last Answer : Radioactive decay follows first-order kinetic. The mean life and half-life of nuclear decay process are `tau = 1 ... B. 53 yrs C. 530 yrs D. 5300 yrs
Last Answer : Radioactive decay follows first-order kinetic. The mean life and half-life of nuclear decay ... exponentially C. parabolically D. all of these
Last Answer : Radioactive decay follows first-order kinetic. The mean life and half-life of nuclear decay ... lambda` depend on the nature of radioactive element
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 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 sample has a half life 1500 years. A sealed tube conataining 1g of the sample will contain after 3000 years,
Last Answer : A radioactive sample has a half life 1500 years. A sealed tube conataining 1g of the sample will contain ... g of the sample D. 0.01g of the sample
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 : How doses the half-life of a radioactive waste affect the Type of container in witch?
Last Answer : Need answer
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
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 : Give reason: Radioactive material of longer half life is dangerous.
Last Answer : Since the radioactivity lasts longer.
Description : Which of the following commonly used radioactive isotopes has the longest half life? a) Iridium 192 b) Cobalt 60 c) Thulium 170 d) Ytterbium 169
Last Answer : b) Cobalt 60
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 : 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 : Which of the following is the same for both radioactive iodine and stable iodine? w) number of neutrons x) mass number y) half-life z) chemical properties
Last Answer : ANSWER: Z -- CHEMICAL PROPERTIES
Description : If a gas absorbs `200J` of heat and expands by `500 cm^(3)` against a constant pressure of `2 xx 10^(5) N m^(-2)`, then the change in internal energy
Last Answer : If a gas absorbs `200J` of heat and expands by `500 cm^(3)` against a constant pressure of `2 xx 10^(5) N ... . `-100 J` C. `+100 J` D. None of these