Chemistry Chapter 7 Flashcards

Questions and Answers

Which equation summarizes the equivalence of energy and matter or mass?

E=mc^2

What does the large value of c^2 mean?

It is possible to obtain a tremendous amount of energy from a very small amount of matter.

What is nuclear fission?

Splitting of a large nucleus into smaller ones with the release of energy.

What occurs when matter 'disappears'?

An equivalent quantity of energy appears. Signup and view all the answers

What is an atom mostly composed of?

Empty space. Signup and view all the answers

What are the three factors that determine whether particular molecules will split?

Size, number of protons and neutrons, energy of neutrons that bombard nucleus. Signup and view all the answers

What are the isotopes of Uranium?

U-238 and U-235. Signup and view all the answers

How is an isotope specified?

With both their mass and atomic numbers. Signup and view all the answers

How is the process of nuclear fission initiated?

By neutrons. Signup and view all the answers

How do you balance a nuclear equation?

Count protons and neutrons, not the atoms. Signup and view all the answers

Which of the following are renewable energy sources? (Select all that apply)

Geothermal power Signup and view all the answers

According to Einstein's equation E=mc^2, matter can be converted into what?

Energy. Signup and view all the answers

How does the process of nuclear fission produce energy?

Mass of the reactants is converted into energy, which is released. Signup and view all the answers

What are renewable energy sources?

Continually and rapidly replenished from natural sources. Signup and view all the answers

Describe how to balance a nuclear equation.

The sum of the mass numbers on both sides must equal, and the sum of the subscripts must also equal. Signup and view all the answers

What is a chain reaction?

A reaction where one of the products is recycled as a reactant and becomes self-sustaining. Signup and view all the answers

What equation is used to calculate the energy released in a nuclear reaction?

ΔE = Δmc^2. Signup and view all the answers

How is electricity generated in a nuclear power plant?

The heat generated by the nuclear reaction is used to generate steam, which drives a turbine to produce electrical energy. Signup and view all the answers

What is the fuel used in a nuclear power station?

UO2 pellets. Signup and view all the answers

Describe the components of a nuclear power plant.

Cooling towers, reactor vessel, control rods, fuel rods. Signup and view all the answers

Which two elements are commonly used as a source of neutrons in nuclear reactors?

Plutonium and beryllium. Signup and view all the answers

What do the control rods in a nuclear reactor absorb?

Neutrons. Signup and view all the answers

Study Notes

Energy-Matter Equivalence

E = mc² illustrates the relationship between energy (E) and mass (m), where c is the speed of light (3.00 x 10⁸ m/s).
c² equals 9.00 x 10¹⁶ m²/s², demonstrating that small amounts of matter can yield vast amounts of energy.

Nuclear Fission

Nuclear fission involves the splitting of a large nucleus into smaller nuclei, releasing energy due to the mass difference.
Mass of products is slightly less than reactants; both mass and energy are conserved.
Heavier nuclei, like uranium and plutonium, may undergo fission, especially when bombarded with high-energy neutrons.

Atoms and Isotopes

Atoms primarily consist of empty space; most mass is concentrated in the dense nucleus.
Uranium always contains 92 protons and has isotopes: U-238 (146 neutrons) and U-235 (143 neutrons).

Factors for Molecular Splitting

Size, number of protons/neutrons, and neutron energy are critical in determining molecular stability and fission potential.
Light stable atoms like oxygen and chlorine do not split, but heavy atoms like uranium do.

Nuclear Reactions and Energy

Nuclear fission can release additional neutrons and initiate chain reactions.
ΔE = Δmc² is used to calculate energy changes, where Δm represents mass change during reactions.
Mass of reactants converts to energy, which is released during nuclear fission.

Balancing Nuclear Equations

Balancing a nuclear equation requires ensuring that the sum of mass numbers and subscripts are equal on both sides.

Renewable Energy Sources

Include solar power, hydroelectric power, and geothermal power, which are naturally replenished.

Nuclear Power Plants

Generate electricity by using heat from nuclear reactions to produce steam that drives turbines.
Components include control rods (that absorb neutrons), fuel rods (containing UO₂ pellets), primary coolant systems, and cooling towers for heat dissipation.

Neutron Sources and Control

Common neutron sources in reactors are plutonium (²³⁸Pu) and beryllium (⁹Be).
Control rods made from materials like boron or cadmium absorb neutrons, helping regulate the nuclear reaction.

Chain Reactions

Chain reactions recycle one product as a reactant, potentially leading to self-sustaining reactions that can be controlled.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on key concepts from Chapter 7 of Chemistry. This quiz covers essential terms such as energy-matter equivalence and nuclear reactions. Perfect for students looking to reinforce their understanding of these important topics.