15. the nucleus of isotope a of an element has a larger mass than isotope b of the same element. the number…
15. the nucleus of isotope a of an element has a larger mass than isotope b of the same element. the number of neutrons in the nucleus of isotope a is ____________ the number of protons in the nucleus of isotope b. a. less than b. greater than c. the same as 16. an atom is electrically neutral when its a. neutrons balance the protons and electrons. b. nuclear forces stabilize the charges. c. numbers of protons and neutrons are equal. d. numbers of protons and electrons are equal. 17. the force between the nucleus and the electron cloud is ____________. the force between the electrons in the electron cloud is ____________. a. repulsive; attractive b. attractive; repulsive c. repulsive; repulsive d. attractive; attractive part 2 open response: answer the following questions in their entirety on your answer sheet. if a question has multiple parts, be sure to clearly label each part. point values are indicated next to each question. (60 pts total) for #21 - 32, match the vocabulary terms with their correct definition. (12 pts) 18. atom a. atoms of the same element with different masses. 19. atomic number b. this contributes to the mass of an atom but not its charge. 20. isotope c. this differs amongst isotopes and thus must be included in their notation. 21. proton d. the smallest unit of an element that still retains its properties. 22. neutron e. this is a row on the periodic table. 23. electron f. the periodic table is arranged by this. 24. quark g. this is a charged atom. 25. mass number h. the weighted average of all of the different isotopes of an element. 26. average atomic mass i. the number of these determines the identity of an atom. 27. group j. the number of these determines the charge and bonding behavior of an atom. 28. period k. this can also be referred to as a family. 29. ion l. the attraction between these holds the nucleus together. 30. differentiate between the plum pudding model and the nuclear model for the atom. (2 pts) 31. differentiate between the bohr model and the electron cloud model for the atom. (2 pts) 32. explain how a bohr model is a helpful tool for visualizing the structure of the atom. include what you can determine about an atoms structure from a bohr model. then include one major short - coming of the model that does not accurately represent an atoms structure. (5 pts) 33. use the information provided and a periodic table to complete the chart on your answer sheet. (8 pts)
Answer
15.
Brief Explanations:
Isotopes of the same element have the same number of protons. Mass differences are due to different numbers of neutrons.
Answer:
C. the same as
16.
Brief Explanations:
An atom is neutral when the positive - charged protons and negative - charged electrons are equal in number.
Answer:
D. numbers of protons and electrons are equal.
17.
Brief Explanations:
The nucleus is positively charged and the electron cloud is negatively charged, so the force between them is attractive. Electrons are negatively charged, so the force between electrons in the electron cloud is repulsive.
Answer:
B. attractive; repulsive
18.
Brief Explanations:
An atom is the smallest unit of an element that still retains its properties.
Answer:
D. The smallest unit of an element that still retains its properties.
19.
Brief Explanations:
The atomic number determines the identity of an atom.
Answer:
I. The number of these determines the identity of an atom.
20.
Brief Explanations:
Isotopes are atoms of the same element with different masses.
Answer:
A. Atoms of the same element with different masses.
21.
Brief Explanations:
Protons determine the charge and bonding behavior of an atom.
Answer:
J. The number of these determines the charge and bonding behavior of an atom.
22.
Brief Explanations:
Neutrons contribute to the mass of an atom but not its charge.
Answer:
B. This contributes to the mass of an atom but not its charge.
23.
Brief Explanations:
Electrons are involved in chemical reactions and are arranged around the nucleus.
Answer:
F. The periodic table is arranged by this.
24.
Brief Explanations:
Quarks are sub - atomic particles that make up protons and neutrons.
Answer:
No match in the given options
25.
Brief Explanations:
The mass number is different amongst isotopes and is included in their notation.
Answer:
C. This differs amongst isotopes and thus must be included in their notation.
26.
Brief Explanations:
The average atomic mass is the weighted average of all of the different isotopes of an element.
Answer:
H. The weighted average of all of the different isotopes of an element.
27.
Brief Explanations:
A group in the periodic table can also be referred to as a family.
Answer:
K. This can also be referred to as a family.
28.
Brief Explanations:
A period is a row on the periodic table.
Answer:
E. This is a row on the periodic table.
29.
Brief Explanations:
An ion is a charged atom. No match in the given options
30.
Brief Explanations:
The plum - pudding model proposed that electrons were embedded in a positively - charged “pudding”. The nuclear model proposed that there is a small, dense, positively - charged nucleus with electrons orbiting around it.
Answer:
The plum - pudding model has electrons embedded in a positive matrix. The nuclear model has a small, dense nucleus with electrons orbiting it.
31.
Brief Explanations:
The Bohr model has electrons in fixed orbits around the nucleus. The electron - cloud model describes the probability of finding an electron in a certain region around the nucleus.
Answer:
The Bohr model has electrons in fixed orbits. The electron - cloud model has electron probability regions.
32.
Brief Explanations:
The Bohr model is helpful for visualizing discrete energy levels and electron orbits. A major shortcoming is that it does not accurately represent the wave - like nature of electrons and the uncertainty in their position.
Answer:
Helpful: Visualizes energy levels and orbits. Shortcoming: Ignores electron wave - like nature and position uncertainty.
For question 33, since no information about the chart is provided, it cannot be answered.