In the thorium decay series that begins with `.^(232)Th,.^(228)Th` alpha-decays into `.^(224)Ra` with a half life of 1.9yr. `.^(224)Ra` alpha-decays into `.^(230)Rn` with a half life of 3.7d, which in turn decays into `.^(216)Po` with a half life of 55s. If the nuclides are in radioactive equilibrium in a mineral sample that contains 1.0g of `.^(220)Rn`, what are the masses of `.^(224)Ra` abd `,^(228)Th` in the sample?
1 Answers
Talk Doctor Online in Bissoy App
In the following radioactive decay `x^(232)rarry^(220)` how many `alpha` and `beta` particles are ejected from x to y?
Correct Answer - C By mean of emission of an `alpha` particle the atomic number is decreased by 2 units while mass number is decreased by 4 units but in case...
2 Answers 1 views
If a variable takes the discrete values `alpha-4`, `alpha -(7)/(2), alpha-(5)/(2), alpha-2,alpha+(1)/(2), alpha-(1)/(2), alpha+5(alpha gt 0)`, then th
Correct Answer - A Arrange the data as follows : `alpha-(7)/(2), alpha-3, alpha-(5)/(2),alpha-2, alpha-(1)/(2),alpha+(1)/(2),alpha+4,alpha+5` Median `=(1)/(2)` [value of 4th item+value of 5th item] `therefore " Median"=(alpha-2+alpha-(1)/(2))/(2)=(2alpha-(5)/(2))/(2)=alpha-(5)/(4)`
2 Answers 1 views
If `A(alpha, beta)=[("cos" alpha,sin alpha,0),(-sin alpha,cos alpha,0),(0,0,e^(beta))]`, then `A(alpha, beta)^(-1)` is equal to
Correct Answer - A We have, `A(alpha, beta)^(-1)=1/e^(beta) [(e^(beta) cos alpha,-e^(beta) sin alpha,0),(e^(beta) sin alpha,e^(beta) cos alpha,0),(0,0,1)]` `=A(-alpha, -beta)`
2 Answers 2 views
Nuclei of `.^(64)Cu` can decay be electron capture (probability 61%) or by `beta^(+)` decay (39%). Half life of `.^(64)Cu` is 12.7 hour. Find the part
Correct Answer - 20.8hr.
2 Answers 1 views
A radioactive nucleus A decay to C after emitting two `alpha` and three `beta` particles. Another nucleus B decays to C by emitting one `alpha` and fi
Correct Answer - (a) `Z_(A)-Z_(B)=4;A_(A)-A_(B)=4` (b) `(9N_(0))/(2)` (c) 6 hr
2 Answers 1 views
A radioactive sample consists of two isotopes one of then decays by `alpha-` emission with a half life of `tau_(1)=405s` and the other one decays by `
Correct Answer - (a) `(1)/(9)` (b) 1215s
2 Answers 1 views
A radioactive nucleus A decays into B with a decay constnat `lambda_(1)`. B is alos radioactive and it decays into C with a decay constant of `lambda_
Correct Answer - (a)`(dN_(2))/(dt)=-lambda_(2)N_(2)+lambda_(1)N_(1)^(0)e^(-lambda_(1)t)` (b) `(A_(2))/(A_(1))=(lambda_(2))/(lambda_(2)-lambda_(1))` (c) `((1)/(lambda_(2)-lambda_(1)))ln((lambda_(2))/(lambda_(1)))`
2 Answers 2 views
Carbon (Z=6) with mass number 11 decays to boron (Z=5).(a) Is it a `beta^+` -decay? (b) the half-life of the decay scheme is 20.3 minutes .How much ti
Correct Answer - `[beta^(+), 64 min]`
2 Answers 1 views
`.^(238)U` decays with a half-life of `4.5 xx10^(9)` years, the decay series eventaully ending at `.^(206)Pb`, which is stable. `A` rock sample analys
Correct Answer - `[38 xx 10^(6) yrs]`
2 Answers 1 views
27^(60)CO decays with half-life of 5.27 years to produce 28^(60) Ni. What is the decay constant for such radioactive disintegration?
Option : a. 0.132 y-1
2 Answers 6 views