which orbital can hold a maximum of 8 electrons

ATI TEAS 7

TEAS 7 practice test science

1. Which orbital can hold a maximum of 8 electrons?

A. s orbital
B. p orbital
C. d orbital
D. f orbital

Correct answer: B

Rationale: The correct answer is the p orbital. Each p orbital can hold a maximum of 6 electrons (2 electrons in each of the 3 p orbitals), totaling 18 possible electrons when considering all three p orbitals. The s orbital can hold a maximum of 2 electrons, the d orbital can hold a maximum of 10 electrons, and the f orbital can hold a maximum of 14 electrons. Therefore, the p orbital is the orbital that can hold a maximum of 8 electrons, making it the correct choice.

2. What are energy levels and orbitals?

A. Energy levels are the paths that electrons travel around the nucleus of an atom, and orbitals are the regions where electrons are most likely to be found.
B. Energy levels are the regions where electrons are most likely to be found, and orbitals are the paths that electrons travel around the nucleus of an atom.
C. Energy levels are the same as orbitals.
D. Energy levels and orbitals do not exist.

Correct answer: A

Rationale: Energy levels refer to the specific energies that electrons in an atom can have, while orbitals are the regions within an atom where electrons are most likely to be found. Electrons do not travel in fixed paths around the nucleus like planets around the sun, as suggested in option B. Option C is incorrect because energy levels and orbitals are distinct concepts in atomic structure. Option D is incorrect as energy levels and orbitals are fundamental concepts in understanding the behavior of electrons in atoms.

3. What cellular process ensures the accurate transmission of genetic material during cell division?

A. Mitosis (somatic cell division)
B. Meiosis (germ cell division)
C. Replication (DNA duplication)
D. Transcription (DNA to RNA conversion)

Correct answer: A

Rationale: Mitosis is the correct answer. Mitosis is the process by which somatic cells divide to produce two identical daughter cells. During mitosis, the genetic material is accurately replicated and distributed to ensure each daughter cell receives a complete set of chromosomes. This process is crucial for growth, repair, and maintenance of multicellular organisms. Meiosis, on the other hand, is the type of cell division that occurs in germ cells to produce gametes (sperm and egg cells), focusing on genetic diversity through recombination and reduction of chromosome number. Replication is the process of copying DNA to produce an identical copy, essential for cell division but not the specific process ensuring accurate genetic material transmission. Transcription involves copying DNA into RNA, crucial for gene expression but not directly related to the accurate transmission of genetic material during cell division.

4. What is the oxidation state of carbon in CH4?

A. +1
B. -1
C. +2
D. -4

Correct answer: D

Rationale: In CH4 (methane), carbon is bonded to four hydrogen atoms. Hydrogen has an oxidation state of +1. Since the overall charge of CH4 is 0, the oxidation state of carbon must be -4 to balance the charges. Each hydrogen contributes an oxidation state of +1, resulting in a total of +4 from hydrogen atoms. To achieve a total oxidation state of 0 for the molecule, carbon must have an oxidation state of -4 to offset the contribution from hydrogen. Therefore, the correct answer is -4. Choices A, B, and C are incorrect: +1 is the oxidation state of hydrogen, -1 is not the oxidation state of carbon in methane, and +2 is not the correct oxidation state of carbon in CH4.

5. Which type of immune cell does the human immunodeficiency virus (HIV) target and destroy?

A. Neutrophils
B. Macrophages
C. Helper T cells
D. Memory B cells

Correct answer: C

Rationale: HIV targets and destroys Helper T cells, which are vital for coordinating the immune response against infections. The destruction of Helper T cells weakens the immune system, leading to acquired immunodeficiency syndrome (AIDS). Neutrophils (Choice A) are primarily involved in acute inflammatory responses and fighting bacterial infections. Macrophages (Choice B) play a role in phagocytosis and antigen presentation but are not the primary target of HIV. Memory B cells (Choice D) are responsible for mounting a quicker and more robust antibody response upon re-exposure to a pathogen, but they are not the main target of HIV infection.