Problem 10 - Chemistry An Atoms First Approach

Question

Which (if any) of the following can be determined by knowing the number of protons in a neutral element? Explain your answer. a. the number of neutrons in the neutral element b. the number of electrons in the neutral element c. the name of the element

Step-by-Step Solution

Answer

By knowing the number of protons in a neutral element: a. We cannot determine the number of neutrons as different isotopes can have the same number of protons but different numbers of neutrons. b. We can determine the number of electrons since, in a neutral element, the number of electrons must equal the number of protons. c. We can determine the name of the element because each element has a unique number of protons that establishes its position in the periodic table and its identity.

Step 1: 1. Recognizing the role of protons in an atom

Protons are the positively charged particles in the nucleus of an atom. A neutral element means that there is no net charge. The number of protons in the nucleus determines the element's atomic number and subsequently, its position in the periodic table. This helps us narrow down the possibilities.

Step 2: 2. Analyzing the relationship between protons and neutrons

Neutrons are the neutral particles in the nucleus of an atom. Knowing the number of protons does not give information on the number of neutrons. Elements with the same number of protons but different numbers of neutrons are called isotopes. Therefore, we cannot determine the number of neutrons by knowing the number of protons.

Step 3: 3. Analyzing the relationship between protons and electrons

Electrons are the negatively charged particles surrounding the nucleus of an atom. Because the element is neutral, the number of positively charged protons must be equal to the number of negatively charged electrons. So, knowing the number of protons also tells us the number of electrons.

Step 4: 4. Analyzing the relationship between protons and the element's name

The number of protons in an atom determines its position in the periodic table and its identity as an element. Each element has a unique number of protons in their nucleus. Therefore, knowing the number of protons also allows us to identify the name of the element. To conclude: a. We cannot determine the number of neutrons in the neutral element by knowing the number of protons. b. We can determine the number of electrons in the neutral element by knowing the number of protons. c. We can determine the name of the element by knowing the number of protons.