Log in
Physics
1
answer
0
watching
71
views

Find to three significant digits the charge and the mass of the following particles. Suggestion: Begin by looking up the mass of a neutral atom on the periodic table of the elements in Appendix C. 

(a) an ionized hydrogen atom, represented as H+

(b) a singly ionized sodium atom, Na+

Watch
1
answer
0
watching
71
views

For unlimited access to Homework Help, a Homework+ subscription is required.

Sumant
SumantLv10
28 Dec 2020

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share

Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

Related questions

A proton and an alpha particle are momentarily at rest at a distance r from each other. They then begin to move apart. Find the speed of the proton by the time the distance between the proton and the alpha particle doubles.

Both particles are positively charged. The charge and the mass of the proton are, respectively e and m. The charge and the mass of the alpha particle are, respectively, 2e and 4m.

Which of the following quantities are unknown?

A. initial separation of the particles

B. final separation of the particles

C. initial speed of the proton

D. initial speed of the alpha particle

E. final speed of the proton

F. final speed of the alpha particle

G. mass of the proton

H. mass of the alpha particle

I. charge of the proton

J. charge of the alpha particle

P2) A uniformly charged sphere of radius R has an electricfield
3
E r
R
= for r < R.
Consider a very simplified model of the atom where the positivenucleus, consisting of Z
protons, is a point charge at the center of the atom, surrounded bya uniform cloud of Z
electrons.
(a) If the nucleus is displaced relative to the electron cloud by asmall distance x, what is
the force acting on the nucleus due to the cloud (and equivalently,the force acting on the
cloud due to the nucleus)?
(b) In PHYS 132 you will have seen simple harmonic oscillators,such as a mass on a
spring. It can be shown that if the acceleration a of an object isdirectly proportional to
its displacement x from a point of equilibrium, then the objectwill undergo simple
harmonic motion with a frequency:
2
f ?
p
= , where 2
a x
?
=-
Determine the frequency of oscillation if the nucleus is displacedrelative to the center of
the electron cloud and then let go. Hint: from knowing the massesof the protons and
electrons, is it the cloud that primarily moves back and forth oris it the nucleus?
Calculate this frequency for a hydrogen atom; you can find theatomic radius R on
Wikipedia. If this oscillating atom emits an electromagnetic waveat the same frequency,
what is its wavelength?

A nuclear reaction is represented by an equation similar to theequation for a chemical reaction. An example of a nuclear reactionis the decay of radium into radon by the emission of an alphaparticle (a helium nucleus). The equation for this reactionis

^{226}_{\ 88}{\rm Ra}\; \rightarrow \, ^{222}_{\ 86}{\rmRn}+\;^4_2{\rm He}.

The superscript preceding each element indicates the nucleon numberof that particular nucleus (total number of protons and neutrons).The subscript indicates the charge of the nucleus, which is equalto the atomic number for nuclei. Nuclear reactions frequentlyinvolve electrons (sometimes called beta rays) and photons(sometimes called gamma rays). Electrons, which have nucleon number0 and charge -1, are represented in equations as either ^{\ \;0}_{-1}\beta or ^{\ \; 0}_{-1}{\rm e}. Photons are represented as^{0}_{0}\gamma to emphasize that they have no nucleon number andcarry no charge.

In nuclear reactions, several conservation laws are usuallysufficient to determine the products or reactants. One of these isconservation of nucleon number. The total number of neutrons andprotons in all of the reactants must be the same as the totalnumber of protons and neutrons in the products. Although protonsand neutrons sometimes change into one another, neither can simplydisappear. Another important conservation law is conservation ofcharge. The net charge of the reactants must be the same as that ofthe products.

Notice that, in our equation for the decay of radium, the sum ofthe nucleon numbers on each side is 226 and the sum of the chargeson each side is 88. If you knew everything in this equation exceptthe isotope of radon produced, you could simply subtract 4 from 226to find the nucleon number required to make the nucleon number ofthe products equal the nucleon number of the reactants. Similarly,if you knew everything in this equation except for the identity ofthe product element, you could simply subtract 2 from 88 and thenlook in a periodic table to find that the element with atomicnumber 86 is radon.

In parts A and B consider the decay of radon by alpha particleemission:

^{222}_{\ 86}{\rm Rn}\;\rightarrow\;X +\,^{4}_{2}{\rm He}.

a. What is the nucleon number of the element X?
Express your answer as an integer.

b. What is the atomic number (nuclear charge) of the elementX?
Express your answer as an integer.

n parts C and D consider the decay of Potassium-43 into calcium-43via the following reaction:

^{43}_{19}{\rm K} \rightarrow ^{43}_{20}{\rm Ca}+\,X.

c. What is the charge of the emitted particle X?
d. is not visible yet

E. An isotope of potassium with a half-life of roughly one billionyears is often used in radioactive dating. This isotope decaysthrough electron capture, the process of drawing an electron intothe nucleus. What is the chemical symbol for the element thatresults from this process? The equation for the reaction is

^{40}_{19}{\rm K}+\,^{\ \;0}_{-1}{\rm e}\rightarrow \,?.
Express your answer as a chemical symbol (e.g., Na forsodium).

f. The reaction energy of a reaction is the amount of energyreleased by the reaction. It is found by determining the differencein mass between the reactants and products and then using E=mc^2 toconvert the lost mass into the released energy.

Look again at the equation for the decay of radium (Ra), given inthe introduction. Use the following table of masses to determinethe reaction energy of this reaction.
Nucleus or particle Mass in atomic mass units
radium-226 226.025402
radon-222 222.017571
alpha particle 4.002602
Express your answer in joules to three significant figures.

please answer fully... thank you

Weekly leaderboard

Home
Homework Help 3,900,000
Physics 110,000
Start filling in the gaps now
Log in