Question

1. in an atom the nucleus contains____. a. all the protons and neutrons b. an equal number of protons and electrons c. only neutron d. only protons 26. protons, neutrons and electrons are examples of__. a. ions b. elements c. compounds d. subatomic particles 27. a neutron has a charge of a. 0 b. -1 c. +1 d. -2 28. the atomic number of barium is__. a. 2 b. 56 c. 5 d. 13 29. a proton has an electrical charge of__. a. 0 b. -1 c. +1 d. -2 30. the atomic number of an atom is equal to the number of a. protons b. protons minus neutron c. neutrons d. neutron plus protons 31. the atomic mass of arsenic is____. a. 7.000 amu b. 33 amu c. 74.922 amu

Explanation:

1. The nucleus of an atom contains all protons and neutrons.
2. Protons, neutrons, and electrons are subatomic particles that make up an atom.
3. A neutron is neutral and has a charge of 0.
4. Barium has an atomic number of 56, which is a known fact from the periodic - table.
5. A proton has a positive charge of +1.
6. The atomic number of an atom is equal to the number of protons.
7. The atomic mass of arsenic is approximately 74.922 amu, which is a value from the periodic - table.

Answer:

1. a. All the protons and neutrons
2. d. Subatomic particles
3. a. 0
4. b. 56
5. c. +1
6. a. Protons
7. c. 74.922 amu