Help in chemistry please!?

PLEASE help me DX

i suck at chemistry and i gotta do well on this assignment X/

1 What one characteristic of an atom determines what type of element it is?

the number of neutrons.

the number of protons.

the mass number.

the atomic mass.

2 Describe the function and usefulness of a model in scientific investigations, using the atomic model as an example.

3 Scientific experiments showed evidence that the mass of an atom was greater than the total mass of its protons. These experiments led to the discovery of the





4 An atom of fluorine has an atomic number of 9 and an atomic mass of 19. The atom contains

19 protons, 19 electrons, and 9 neutrons.

19 protons, 10 electrons, and 9 neutrons.

9 protons, 10 electrons, and 10 neutrons.

9 protons, 9 electrons, and 10 neutrons.

5 Use the development of the atomic model to explain how scientists refine and build off each other's findings, in order to develop a theory.

6 Summarize the five points of Dalton's atomic theory, and explain at least one change that occurred to the atomic theory because of further experimentation.

7 A given atom has 3 protons, 4 neutrons, and 3 electrons. Describe how you can use those three values to describe the structure, charge, and mass of the atom.


1) number of protons( aka atomic number)

2) Atomic model shows us how electrons orbit around the nucleus, show us how many are on each orbit, shows us the number of electrons, protons, and neutrons.

3) nucleus

4) 9 protons, 9 electrons, 10 neutrons

5) Using the atomic model brought the periodic table, and later one brought electroegativity, ionization energies, metallic behaviors.

6) You gotta hit the book for this one X.x don't remember.

7) mass of atom= proton+neutron (7), charge is zero (because the protons and electrons balance out), the structure you will have to construct with atomic model (nucleus has 3 protons, 4 neutrons), and the orbitals have 3 electrons.