1. Which statement about subatomic particles is NOT true? (1 point)
Protons and neutrons have almost the same mass.
Protons and electrons have opposite charges.
Unlike protons and electrons, neutrons have no charge.
Protons and neutrons have the same charge.
2. Which of the following is unique for any given element? (1 point)
the number of neutrons
the charge on the electrons
the number of protons
the mass of a neutron
3. Suppose an atom has a mass number of 35. Which statement is true beyond any doubt? (1 point)
The atom has an odd number of neutrons.
The atomic number is less than 17.
The atom is not an isotope.
The number of protons in the nucleus
does not equal the number of neutrons.
5. In Rutherford’s gold foil experiment, some of the____________________aimed at gold atoms bounced back, suggesting that a solid mass was at the center of the atom. (1 point)
6. Neutrons and_______________have almost the same mass. (1 point)
7. Which of the three subatomic particles—proton, electron, or neutron—has the least mass? (1 point)
8. If an atom has 32 protons and 38 neutrons, what is its mass number? (1 point)
9. Most calcium atoms have an atomic number of 20 and a mass number of 40, but some calcium atoms have a mass number of 48. What word could you use to describe these two kinds of calcium atoms? (1 point)
10. In the nucleus of an atom, there are 15 protons and 16 neutrons. What is the atomic number of this isotope? (1 point)
Science - DrBob222, Friday, October 10, 2008 at 2:39pm
We don't do your homework for you. We will be happy to help you get started if you show us what you don't understand. Pick ONE problem and tell us what you are having trouble with. Then we can talk about the other nine.
Science - Cheryl, Friday, October 10, 2008 at 3:18pm
I need information on plants. "Explain the roles different parts of a plant have in converting light energy into chemical energy." I need to teach this to a special education child in as simple terms as is possible. Can you tell me some sites I can look at to find information so I can acclamate the information into simpler words for understanding for the "APA" reports for the state of New Jersey.
Science - christinachka, Monday, November 24, 2008 at 9:10pm
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