Question

question 7 (5 points)
listen
in which of the following cases does an atom have a positive charge?
a) there are more protons than electrons.
b) there are more electrons than protons.
c) there are more neutrons than electrons.
d) there are more electrons than neutrons.
question 8 (5 points)
listen
in the nineteenth century, what was known about atoms?
a) the exact structure of all atoms
b) the half - life of all atoms
c) the atom determines the chemical property of an element.
d) the number of atoms that exist in the world is increasing.

Explanation:

For Question 7: Protons have a positive charge and electrons have a negative charge. When there are more protons than electrons, the atom has a net positive charge.
For Question 8: In the 19th - century, it was known that the atom determines the chemical property of an element. The exact structure of all atoms was not known then, nor was the half - life of all atoms (radioactivity and half - life concepts were developed later), and the number of atoms in the world is conserved according to the law of conservation of mass.

Answer:

Question 7: A. There are more protons than electrons.
Question 8: C. The atom determines the chemical property of an element.