Question

exam 2
on this exam, you will figure out the protons, neutrons and electrons of the following
elements and you will select the diagram of what they look like. you may use only your
periodic table.
question 1: standard c.pm.2
how many protons are in boron?
a. 3
b. 4
c. 5
d. 6
question 2: standard c.pm.2
how many electrons are in boron?
a. 3
b. 4
c. 5
d. 6
question 3: standard c.pm.2
how many neutrons are in boron? (hint: use the atomic mass of 11 to find your answer)
a. 3
b. 4
c. 5
d. 6
question 4: standard c.pm.2
which of these is the bohr model for boron?
a.
b.
c.
d.

Explanation:

Question 1

The atomic number of an element is equal to the number of protons. Boron has an atomic number of 5, so it has 5 protons.

In a neutral atom, the number of electrons is equal to the number of protons. Boron has 5 protons, so it has 5 electrons.

Step1: Recall the formula for neutrons

The number of neutrons is calculated as \( \text{Atomic Mass} - \text{Atomic Number} \).

Step2: Identify values for Boron

Atomic mass (given) is 11, atomic number (protons) is 5.

Step3: Calculate neutrons

\( 11 - 5 = 6 \)? Wait, no, wait. Wait, Boron's atomic mass is approximately 11, and atomic number is 5. So neutrons = 11 - 5 = 6? Wait, no, maybe I made a mistake. Wait, Boron has isotopes, but the hint says use atomic mass 11. So 11 (atomic mass) - 5 (protons) = 6? Wait, but the options have d.6. Wait, let's check again. Wait, maybe the atomic mass here is 11, so neutrons = 11 - 5 = 6. So the answer should be d.6? Wait, no, wait, maybe I confused. Wait, Boron's atomic number is 5 (protons = 5). Atomic mass is sum of protons and neutrons. So neutrons = atomic mass - protons. If atomic mass is 11, then 11 - 5 = 6. So the answer is d.6? Wait, but the options are a.3, b.4, c.5, d.6. So yes, d.6.

Answer:

c. 5

Question 2