Question

1)A certain radioactive atom has 90 protons and 142 neutrons. If this atom undergoes alpha decay, what is the mass number of the daughter atom?
The mass number of the daughter atom is __________

2)Which statements correctly describe the process of nuclear fusion?

It happens only to large atoms.
It occurs naturally in the Sun.
It releases a large amount of energy.
It bonds atoms together to create molecules.
It involves the joining of two atomic nuclei.

3)How does a nuclear reactor produce electricity?

A.
High-energy gamma rays are converted by a generator into electricity.
B.
The heat from the reaction turns water to steam, which runs a generator.
C.
The reaction produces a stream of electrons that flow through wires and into batteries.
D.
The heat released from the reaction is used to burn coal or gas to produce electricity.
E.
Control rods absorb the neutrons emitted and release a stream of electrons as electricity.

4)What are some applications of fission reactions?

as a zero-waste energy source
for generating large amounts of heat
for creating stable elements from unstable ones
for creating new, heavier elements
as the energy source in nuclear weapons

5)Which statement best describes the function of enzymes?

A.
Enzymes aid biological reactions by providing more reactants.
B.
Enzymes aid biological reactions by removing products quickly.
C.
Enzymes raise the temperature in a cell to speed up biological reactions.
D.
Enzymes reduce the activation energies of biological reactions.
E.
Enzymes reduce the energy of products in biological reactions.

Answer 1

One

An alpha decay is the loss of a Helium Nucleus which means you lose 2 protons and 2 neutrons. The mass will go down by 4 and the number by 2

The mass number will be 138.

Two

The correct answer is E. It involves ramming together two nuclei to form one bigger and better(?) element. Huge amounts of energy are involved.

Three

The answer is A. Gamma rays have a tremendous amount of energy and the fission decay is very short. An awful of change in a short period of time makes for a good way to produce electricity. That is a very short description of what actually happens.

Four

It's choice One.

and choice 4 if you are talking about fission reactors.

Five

Biology is just about my weakest subject. I have not one class, but I think the function of enzymes is B. They speed up a reaction. What bothers me is that I think they could also do D. Since I have until Friday, I'm going to take this question and ask someone I trust to give me the answer. If I change my mind or he has anything to say about D, I'll leave a comment.

Answer 2

1) Alpha decay

Alpha decay is the loss of a helium nucleus, which consists of two protons and two neutrons (mass number 4).

The radioactive atom will lose four nucleons, so the daughter atom will have a mass number A = 142 - 4 = 138.

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2) Nuclear fusion

• B. Occurs naturally in the Sun
• C. Releases a large amount of energy
• E. Involves the joining of two nuclei.

A. It involves the joining of two small nuclei into a bigger one

D. It does NOT bond atoms together to make molecules . Electrons do that.

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3) Nuclear reactors

B. Correct. In a nuclear reactor, the heat from the reaction turns water to steam, which runs a generator.

A. Wrong. High-energy gamma rays are like X-rays. I don’t think we have the technology to do this yet on a large scale.

C. Wrong. It is not the nuclear reaction but the generators that produce the electrons that flow through wires.

D. Wrong. The nuclear power plants are designed to replace coal- and gas-burning plants.

E. Wrong. Control rods absorb the neutrons emitted and prevent the nuclear reaction from running away uncontrollably.

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4) Applications of fission reactions

Fission reactions

• B. Generate large amounts of heat  
• E. Are the energy source in nuclear weapons

A. Wrong. Fission reactions generate high-level radioactive waste.

C. Wrong. Fission products are more stable than the parent nuclei, but they are stil radioactive (unstable).

D. Wrong. Fission does not create heavier elements. Instead, it splits heavy nuclei into lighter elements.

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5) Enzymes

D. Correct. Enzymes reduce the activation energies of biological reactions.

A. Wrong. Enzymes do NOT provide more reactants ….

B. Wrong. …nor do they remove products quickly

C. Wrong. Enzymes do not raise the temperature of a cell …

E. Wrong. … nor do they change the energy of the products.

Their only function is to act as biological catalysts. They provide alternate pathways with lower activation energies for biological molecules to react.