Here are the correct answers for each question:
Question 1:
D) the number of protons
The atomic number of an atom represents the number of protons in its nucleus.
Question 2:
A) The atomic number is the number of protons, which is always a whole number.
Atomic numbers are whole numbers because they count the discrete number of protons in an atom.
Question 3:
A) So that elements with similar properties are aligned in the same column.
The periodic table is organized so that elements with similar chemical properties are arranged in columns (groups).
Question 4:
C) They are arranged to highlight similarities between different elements.
Elements on the periodic table are arranged based on their atomic number and properties to showcase similarities.
Question 5:
C) An element with 11 protons, 11 neutrons, and 11 electrons.
An element with 11 protons is sodium (Na), which is in the same group (alkali metals) as lithium (Li) and would have similar chemical properties.
Feel free to ask if you have any more questions!