Question

fill in the grid for the element arsenic: *some may be used more than one, some might not be used at all! 33 41 42 74 74.95 75 atomic mass # of protons # of electrons # of neutrons atomic number

Explanation:

Step1: Recall atomic number property

The atomic number of an element is unique and equal to the number of protons. Arsenic (As) has an atomic number of 33, so the number of protons is 33.

Step2: Recall electron - proton relationship

In a neutral atom, the number of electrons is equal to the number of protons. So for arsenic, the number of electrons is also 33.

Step3: Determine atomic mass and neutron number

The atomic mass of arsenic is approximately 74.95. The mass number (a whole - number approximation of atomic mass) is often rounded to the nearest whole number, which is 75 for arsenic. The number of neutrons is calculated as mass number - number of protons. So, number of neutrons = 75 - 33=42.

Answer:

Property	Value
# of Protons	33
# of Electrons	33
# of Neutrons	42
Atomic number	33