CHE 105/110 Introduction to Chemistry - Exercises and Answers

1.

According to Einstein’s equation, the conversion of 1.00 g of matter into energy generates how much energy?

1.

9.00 × 10¹³ J

3.

In the spontaneous fission of lead-208, the following reaction occurs:

²⁰⁸Pb → ¹²⁹I + ⁷⁶Cu + 3¹n

For every mole of lead-208 that decays, 0.1002 g of mass is lost. How much energy is given off per mole of lead-208 reacted?

3.

9.02 × 10¹² J

5.

Recalculate the amount of energy from Exercise 3 in terms of the number of grams of lead-208 reacted

5.

4.34 × 10¹⁰ J/g

7.

What is the energy change of this fission reaction? Masses in grams are provided.

$$\underset{241.0569}{{}^{\text{241}}\text{Pu}}\to \underset{139.9106}{{}^{\text{14}0}\text{Ba}} +\underset{89.9077}{{}^{\text{9}0}\text{Sr}} +\underset{11\times 1.0087}{{\text{11}}^{\text{1}}\text{n}}$$

7.

−1.28 × 10¹³ J

9.

The two rarer isotopes of hydrogen—deuterium and tritium—can also be fused to make helium by the following reaction:

²H + ³H → ⁴He + ¹n

In the course of this reaction, 0.01888 g of mass is lost. How much energy is given off in the reaction of 1 mol of deuterium and tritium?

9.

1.70 × 10¹² J

11.

Briefly describe how a nuclear reactor generates electricity.

11.

A nuclear reactor controls a nuclear reaction to produce energy in usable amounts. The energy produced generates steam, which is used to turn a turbine that generates electricity for general use.

13.

What is a chain reaction?

13.

a process that generates more reaction pathways for each previous reaction