Question

cora wants to draw a model of an atom for her project for the science fair. she wants to draw an atom that has two protons, four neutrons, and two electrons. which model is like coras?

Explanation:

Identify the target subatomic particle counts

Using the Atomic Structure Counting knowledge point

• Protons: 2 (represented by blue spheres with a "+" sign in the nucleus)
• Neutrons: 4 (represented by red spheres in the nucleus)
• Electrons: 2 (represented by green spheres with a "-" sign in the outer shells)

Analyze the first model (left)

• Nucleus: 2 blue protons, 2 red neutrons
• Shells: 4 green electrons
• This does not match Cora's requirements.

Analyze the second model (middle)

• Nucleus: 2 blue protons, 4 red neutrons
• Shells: 2 green electrons
• This matches Cora's requirements exactly.

Analyze the third model (right)

• Nucleus: 4 blue protons, 2 red neutrons
• Shells: 2 green electrons
• This does not match Cora's requirements.

Answer:

• (A) Model with 2 protons, 2 neutrons, and 4 electrons
• (B) Model with 2 protons, 4 neutrons, and 2 electrons (Correct answer)
• (C) Model with 4 protons, 2 neutrons, and 2 electrons