1. Which of the following best describes an atom?
A) protons and electrons grouped together in a random pattern
B) protons and electrons grouped together in an alternating pattern
C) a core of protons and neutrons surrounded by electrons*
D) a core of electrons and neutrons surrounded by protons
4. When trying to identify an unknown element, a scientist determines what other elements the unknown element reacts with chemically. Which property of the unknown element determines the other elements it reacts with?
A. The total number of neutrons in the unknown element
B. The total number of particles in the nucleus of the unknown element
C. The number of protons in the nucleus of the unknown element
D. The number of valence electrons in the unknown element*
5. A researcher wants to experiment with an element that reacts like phosphorus (P) but has a greater atomic mass. Which element should the researcher selected for the experiment (use the periodic table)?
A Nitrogen (N)
B Sulfur(S)
C Arsenic (As)
D Silicon (Si)
What are your answers?
Number 5: use the periodic table. which element is in the same family?
others are correct.
oooppsss! Sorry! I see your answers now : )
oh sorry my answers for number 5 is C
I agree that As is the choice to compare with P.
Thank you
1. The correct answer is C) a core of protons and neutrons surrounded by electrons.
To understand why, let's break down the structure of an atom. Atoms are the basic building blocks of matter, and they consist of three subatomic particles: protons, neutrons, and electrons. Protons are positively charged particles found in the nucleus, or the core, of an atom. Neutrons, on the other hand, are neutral particles also found in the nucleus. Electrons are negatively charged particles that orbit around the nucleus in specific energy levels or shells.
Option A, where protons and electrons are grouped together in a random pattern, is incorrect because the electrons do not randomly group around protons; rather, they occupy specific energy levels.
Option B, where protons and electrons are grouped together in an alternating pattern, is also incorrect as it doesn't accurately represent the structure of an atom.
Option C correctly describes the core of an atom consisting of protons and neutrons, with electrons surrounding it in energy levels. This arrangement is referred to as the planetary model or the Bohr model of the atom.
Option D, with a core of electrons and neutrons surrounded by protons, is incorrect. The protons cannot surround the electrons as the protons reside in the nucleus.
4. The correct answer is C) The number of protons in the nucleus of the unknown element determines the other elements it reacts with.
When trying to identify an unknown element, a scientist looks at its chemical reactions with other elements. This is because the chemical behavior of an element is primarily determined by the number of protons in its nucleus, which is also known as its atomic number. The atomic number defines the element's position on the periodic table and gives it unique chemical properties.
Chemical reactions occur when elements gain, lose, or share electrons to achieve a stable electron configuration. The number of protons directly affects the arrangement of electrons in the atom, thus determining how the element interacts with other elements. Elements with the same number of protons have similar chemical properties because they exhibit similar electron configurations.
Therefore, the number of protons in the nucleus of the unknown element is the property that determines the other elements it reacts with.
5. The correct answer is C) Arsenic (As).
To determine which element reacts like phosphorus (P) but has a greater atomic mass, we need to consider the elements in the same group, or column, as phosphorus on the periodic table. Phosphorus is in Group 15, also known as the Nitrogen group or the Pnictogens.
Looking at the periodic table, we find that the element in Group 15 with a greater atomic mass than phosphorus is arsenic (As). Arsenic has an atomic number of 33, while phosphorus has an atomic number of 15. The atomic mass increases as you move down the group because there are more protons, neutrons, and electrons in the atoms of the elements lower in the group.
Therefore, if a researcher wants to experiment with an element that reacts like phosphorus but has a greater atomic mass, they should select arsenic (As) from the periodic table.