FREE PHYSICAL SCIENCE AND STUDY GAMES ABOUT

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FREE PHYSICAL SCIENCE AND STUDY GAMES ABOUT

MODULE 13 EXAM QUESTIONS

Actual Qs and Ans Expert-Verified Explanation

This Exam contains:

-Guarantee passing score -31 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation

Question 1: List the number of protons, electrons, and neutrons for each -

Neon-20 (neon's chemical symbol is "Ne")

Answer:

Ne, chart says the atom has 10 protons This tells us there are also 10 electrons. The mass number is the sum of protons and neutrons in the nucleus. Thus, there are also 10 neutrons.

Question 2: Why is the strong nuclear force such a short-range force?

Answer:

The strong nuclear force is governed by the exchange of pions. Since pions have a very short lifetime, the strong nuclear force can only act over very tiny distances.

Question 3: Atomic number

Answer:

The number of protons in an atom

Question 4: List the number of protons, electrons, and neutrons for each -

139 La

Answer:

Since the chemical symbol is La, we can use chart and it says the atom has 57 protons. This tells us there are also 57 electrons. The mass number is the sum of protons and neutrons in the nucleus. Thus,

there are 82 neutrons.Question 5: An atom has an atomic number of 34. How many protons and electrons does it have? What is its symbol?

Answer:

The atomic number is defined as the num of protons in an atom. Atoms have the same num of electrons as protons. Thus - 34 electons and 34 protons. Atoms with atomic number of 34 are symbolized with Se.

Question 6: Nucleus

Answer:

The center of an atom, containing the protons and neutrons Question 7: What force keeps the protons and neutrons in the nucleus? What causes this force?

Answer:

The nuclear force. This force is caused by the exchange of pions between protons and/or neutrons.

Question 8: Which of the following atoms are isotopes?

112 Cd, 112 Sn, 120 Xe, 124 Sn, 40 Ar, 120 Sn

Answer:

isotopes must have same number of protons but diff numbers of neutrons. Only atoms with the same chemical symbol can be isotopes. In order to be isotopes atoms must have the same chemic symbol but diff mass nos. So, 112 Sn, 124 Sn, and 120 Sn are isotope

Question 9: What force keeps the electrons orbiting around the nucleus?

Answer:

The electromagnetic force.Question 10: A radioactive isotope goes through radioactive decay, but the isotope's number of protons and neutrons does not change. What kind of radioactive decay occurred?

Answer:

Only gamma decay does not affect the number of neutrons and protons in a radioactive isotope.

Question 11: The three constituents of the atom from least to most massive.

Answer:

Electron, proton, and neutron.

Question 12: Two atoms are isotopes. The first has 18 protons and 20 neutrons. The second has 22 neutrons. How many protons does the second atom have?

Answer:

In order to be isotopes, the two atoms must have the same number of protons. Thus, the second atom also has 18 protons.Question 13: What is the largest Bohr orbit in a uranium atom (the symbol for uranium is "U") and how many electrons are in it?

Answer:

All Uranium atoms have 92 protons and 92 electrons. First 2 electrons in 1st. Next 8 in 2nd. Next 18 in 3rd. Next 32 in 4th. 60 electrons. remaining 32 in 5th. Largest orbit 5th - can hold up to 50 electrons.

Question 14: Half-life

Answer:

The time it takes for half of the original sample of a radioactive isotope to decay

Question 15: List the number of protons, electrons, and neutrons for each -

24 Mg

Answer:

Since the chemical symbol is Mg, we can use the chart to learn that the atom has 12 protons. This tells us that there are also 12 electrons. The mass number is the sum of protons and neutrons in the nucleus. Thus, there are 12 neutrons.

Question 16: what would the Bohr model of a 25 Mg atom look like?

Answer:

All atoms with Mg have 12 protons. There are 12 electrons. 2 of them can go into the first Bohr orbit, 8 can go in the 2nd Bohr orbit. We have to put the other 2 in the 3rd orbit. The 3rd orbit can hold up to 18 electrons. Mass # indicates 13 neutrons.Question 17: The half life of the radioactive decay of 226 Ra is 1,600 years. If a sample of 226 Ra originally had a mass of 10 grams, how many grams of 226 Ra would be lefllt over 3,200 years?

Answer:

In 1,600 years the 10 grams will be cut in half to 5 grams. In the next 1,600 years, those 5 grams will be cut in half to 2.5 grams. That's a total of 3,200 years, so the answer is 2.5 grams.

Question 18: The half-life of the man-made isotopes 11C is 20 minutes. If a scientist makes 1 gram of 11C, how much will be left in one hour?

Answer:

In one hour, the 11C will have passed through 3 half lives. During the 1st half life, the 1 gram sample will reduce to 0.5 grams. During the next half-life, those 0.5 g will reduce to 0.25 grams. In final half-life, those 0.25 g will reduce to 0.125 g.Question 19: Determine the daughter products produced in the alpha decay of the two

radioactive isotopes show below:

224 Ra

Answer:

224 Ra - has 88 protons. This means, 136 neutrons. In alpha decay, the nucleus loses 2 protons and 2 neutrons. This results in an atom with 86 protons and 134 neutrons, or 220 Rn.Question 20: List the 3 types of radioactive particles in this mod in order of their ability to travel through matter. Start with the particle that cannot pass through much matter before stopping, and end with one that can pass through most matter before stopping.

Answer:

Alpha particles pass through the least amount of matter before stopping, beta particles are next, and gamma rays pass through the most matter before stopping.Question 21: Determine the daughter products produced in the beta decay of the two

radioactive isotopes shown below:

• 98 Tc
• 125 I

Answer:

• 98 Tc has 43 protons. 55 neutrons. In beta decay, a neutrons turns into a proton. 44 protons and 54

neutrons or 98 Ru.

• 125 I has 53 protons. 72 neutrons. In beta decay, neutron turns to proton. so, 54 protons and 71

neutrons or 125 Xe.

Question 22: Element

Answer:

A collection of atoms that all have the same number of protons