物理原子模型 DSE、CE 選擇題

1.

A ${}^{238}_{92}\mathrm{U}$ nuclide undergoes a certain number of $\alpha$ and $\beta$ decays and becomes ${}^{210}_{82}\mathrm{Pb}$ . Find the number of $\beta$ particles emitted.

2.

The diagram shows the mass number and atomic number of a radioactive nuclide $K$ . After undergoing the following decays, it becomes $Z$ . $K\xrightarrow{\alpha}X\xrightarrow{\beta}Y\xrightarrow{\gamma}Z$ Which of the following nuclides represents $Z$ ?

Grid of mass number (230 to 235) against atomic number (80 to 85) with points K, Q, S, R and P

3.

$X\xrightarrow{\alpha}Y\xrightarrow{\beta}Z$

The above shows part of a decay series. Which of the following deductions is/are correct ?

(1)

X

and

Z

are isotopes of the same element.

(2)

X

has two more neutrons than

Z

.

(3)

Z

has one more proton than

Y

.

4.

In the upper atmosphere, neutrons are produced by the action of cosmic rays. These neutrons interact with nitrogen nuclei as shown in the following reaction: ${}^{1}_{0}\mathrm{n}+{}^{14}_{7}\mathrm{N}\to X+{}^{1}_{1}\mathrm{H}$ Element $X$ will then emit a $\beta$ particle. The nuclear reaction is as follows : $X\to Y+{}^{0}_{-1}\beta$ . What is the final product $Y$ ?

5.

Some fresh foods are exposed to $\gamma$ radiations from radioactive isotopes for a short time so that the micro-organisms in the foods can be killed. Why are the irradiated foods not harmful to people who eat them ?

6.

$X\xrightarrow{\alpha}Y\xrightarrow{\beta}Z$

$P\xrightarrow{\beta}Q\xrightarrow{\beta}R\xrightarrow{\alpha}S$

In the above two decay series, $P$ and $Y$ are two isotopes of the same element. Which of the following pairs of nuclides may be isotopes ?

(1)

X

and

R

(2)

Y

and

S

(3)

Z

and

Q

7.

A thorium nucleus ( ${}^{234}_{90}\mathrm{Th}$ ) decays by emitting a $\beta$ particle to form a daughter nucleus $X$ . Which of the following equations represents this decay ?

8.

In order to detect cracks in an underground oil pipe, an engineer proposes adding a radioactive source to the oil. Which of the following sources is most suitable ?

9.

Which of the following are essential criteria in choosing radioactive sources as medical tracers in human bodies ?

(1)The sources should have a short half-life.

(2)The radiation emitted should have a weak ionizing power.

(3)The radiation emitted should not be deflected by an electric field.

10.

A radioactive isotope ${}^{234}_{90}\mathrm{Th}$ undergoes a series of decay processes to form a daughter ${}^{206}_{82}\mathrm{Pb}$ . How many $\alpha$ -particles and $\beta$ -particles have been emitted in this decay process ?

	No. of $\alpha$ -particles	No. of $\beta$ -particles
	$6$	$7$
	$7$	$6$
	$7$	$8$
	$8$	$7$