Question

A student looks up an element on the periodic table. The table says that the atomic number of the element is 12 and the mass number of the element is 40. What information do these two numbers convey about the element?(1 point)
Responses

The element has 40 protons and 12 neutrons
The element has 40 protons and 12 neutrons

The element has 12 protons and 12 neutrons
The element has 12 protons and 12 neutrons

The element has 12 protons and has 28 neutrons
The element has 12 protons and has 28 neutrons

The element has 28 protons and 40 neutrons
The element has 28 protons and 40 neutrons
Question 2
In order for an atom to be considered "neutral", which of the following must be true? (1 point)
Responses

There are more protons than electrons
There are more protons than electrons

There are more neutrons than protons
There are more neutrons than protons

The number of protons and neutrons must be the same
The number of protons and neutrons must be the same

The number of protons and electrons must be the same
The number of protons and electrons must be the same
Question 3
In all elements in a group, the thing that is the same is the: (1 point)
Responses

Number of protons
Number of protons

Number of electrons in the valence shell
Number of electrons in the valence shell

Number of neutrons
Number of neutrons

Number of electrons

Answer 1

Q1: The element has 12 protons and 28 neutrons.
- (Mass # 40 = protons + neutrons, atomic # 12 = protons → neutrons = 40 − 12 = 28.)

Q2: The number of protons and electrons must be the same.
- (Neutral atom: positive charges from protons balance negative charges from electrons.)

Q3: Number of electrons in the valence shell.
- (Elements in the same group have the same number of valence electrons.)