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Answer:

What is the mass number?

What is the number of neutrons?

Typically the number of neutrons is the same as the number of protons with the exception of isotopes.

But this is an isotope so take the mass number and subtract the protons from it.

67-30 = 37

What is the number of electrons?

Take the charge into account (2+)

So that means there are two less electrons than there should be so 30-2=28

What is the atomic number?

Atomic number is the same as the proton number

Which of the following statements is INCORRECT regarding nuclear reactions?

Select one:

Select one:

Select one:

Select one:

The positively charged protons in the nucleus are held together by the strong force made possible by the presence of neutrons. Based on the graph in the supplement, which of the following statements are correct?

Select one or more:

Predict the mode of decay and the product for ^{32}Si. (You need your periodic table for this and the following questions.)

Select one or more:

Predict the mode of decay and the product for ^{227}Ac.

Select one or more:

Predict the mode of decay and the product for ^{22}Na.

Select one or more:

To get to a stable nucleus, there may be a series of decays involving alpha and beta particles. How many alpha particles are emitted in the decay series that begins with ^{237}Np and finally produces the stable isotope ^{209}Bi?

Hint, take the time to write and balance the equation using Z and A.

Hint, take the time to write and balance the equation using Z and A.

^{237}Np ------> 7 ^{4}He + ^{209}Bi + 4 ^{0}e

93 2 83 -1

How many beta particles are emitted?

^{130}I decays by emission of beta particles to form stable ^{130}Xe. A 3.00 g iodine sample containing some I-130 was recorded as having 1829 disintegrations per min. k = 0.00094 min ^{-1}. How many radioactive I-130 atoms are present in the sample?

Hint, just use R = kN and solve for N.

1829 = 0.00094(N)

N=1945744.681

The radioactive decay of a sample containing an unknown radioactive isotope produced 8898 disintegrations per minute. 10.17 days later, the rate of decay was found to be 2898 disintegrations per minute. Calculate the half-life in days for the unknown radioactive isotope.

ln (Rt/Ro) = -kt

R0=8898d/min * 1440 min/day = 12813120

Rt= 2898*1140=3303720

ln (3303720/12813120) = -k(10.17)

k=0.110

t1/2 = 0.693/k = 6.28

A certain radioactive element has a half life of 7403 years. How much of a 7.76 g sample is left after 8663 years?

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The half-life of carbon-14 is 5,730 years. An artifact produces 13.9 disintegrations of ^{14}C per minute per gram of carbon in the sample. Estimate the age of this sample assuming that its original radioactivity was 15.3 disintegrations per minute per gram of carbon.

t1/2 = 0.693/k=5730

k=0.0001209

ln(13.9/15.3)= -0.0001209t

t=793.468

What is the energy released when 0.771 g are converted to energy? Express your answer in joules. For self-consistent units you must use kg because 1 J = 1 kg m^{2}/s^{2}.

E=mc^2

=0.771(3e8)^2

=6.939e16

# of neutrons =14

# of protons =13

14*1.008665 - 14.12

13*1.007825=13.10

13.10+14.12=27.2333

mass defect = 27.223 - 26.9815

=0.2415

What is the nuclear binding energy per mole if the mass defect of a certain isotope is 0.0800 u per atom or 0.0800 g per mol? Express your answer in joules. Remember to use self-consistent units.

E=mc^2

=(0.0800g/mol * 1kg/1000g) * (3e8)^2=7.2e12