Question

Check chemistry homework sheet

Answer 1

1. Nuclear decay by alpha particle emission is more common in atoms of elements that:
a have an atomic number greater than 83 <-----
b have a proton to neutron ratio of greater than 3:1
c have an atomic number less than 83
d have more electrons than protons

2. Identify the missing particle in the following equation: 3/2He + 3/2He -> 2 1/1He + ____
(3/2He refers to 3 above 2 next to He as an isotope symbol)
a 2/1He
b 1/1He
c 5/3Li <----
d 4/2He

3. One of the major drawbacks to using nuclear fission as a reliable energy source is:
a There is not enough energy produced by this method to make it profitable.
b The process cannot be well-controlled.
c The intense amount of heat require to initiate the reaction.
d The products are more radioactive than the reactants. <---

4. Which of the following concerns apply to nuclear fission reactions?
a concern about the disposal of nuclear waste
b concern about the safe operation of nuclear plants
c concern about nuclear weapons proliferation
d all of these are concerns <----

5. The energy output of the Sun and other stars is a result of fission reactions among hydrogen nuclei.
True
False <---

6. Why is the total mass of a helium nucleus not equal to the mass of its individual parts? (Points : 3)
a The "missing" mass is due to inaccurate measurement on a very small scale.
b The "missing" mass has been converted to energy. <----
c The "missing" matter has been converted to mass.
d The "missing" mass has been converted to matter. <----

7. In a nuclear reaction, the mass-energy of the reactants is generally: (Points : 3)
a less than the mass-energy of the products <----
b equal to the mass of the products
c equal to the energy of the products
d equal to the mass-energy of the products

8. A mass of 10.0 kilograms is completely converted into energy. What is this amount of energy in joules? (1 J = 1 kg m2/s2) (Points : 3)
a 3.33 x 10^8 J <----
b 1.11 x 10^-8 J
c 3.00 x 10^16 J
d 9.00 x 10^17

9. A mass of 4.00 kilograms is completely converted into energy. What is this amount of energy in joules? (1 J = 1 kg m2/s2) (Points : 3)
a 1.20 x 10^9 J
b 1.33 x 10^-8 J
c 3.60 x 10^17 J
d 4.4 x 10^-16 J <----
Had trouble with this one^....

10. According to Einstein's formula for the conversion of mass and energy, to find the energy, multiply the mass by the speed of light. (Points : 2)
True <----
False

Answer 2

looks good

Answer 3

yup! they all are correct
well done

Answer 4

Are you sure ? @RANE

Answer 5

yes