TEAS 7 Chemistry: Essential Practice for Success

ATI TEAS 7

Chemistry

1. What is the formula for calculating molarity?

A. M = n/V
B. M = n/L
C. M = mol/L
D. M = mol/dmÂ³

Correct answer: a

Rationale: All of these choices are equivalent to the original formula. The symbol "n" represents the number of moles of solute, and the symbol "V" represents the volume of the solution in liters. The symbol "L" is an abbreviation for "liters," and "dmÂ³" is an alternative way to represent liters.

2. Which of the following properties is NOT characteristic of a covalent bond?

A. Sharing of electrons between atoms
B. High melting and boiling points
C. Low electrical conductivity in solid state
D. Directional bonding

Correct answer: B

Rationale: Covalent bonds are formed by the sharing of electrons between atoms. This sharing results in the formation of molecules with directional bonding, where the atoms are held together in a specific orientation. Covalent compounds generally have low melting and boiling points compared to ionic compounds, as the intermolecular forces in covalent compounds are weaker. Additionally, covalent compounds do not conduct electricity in the solid state because the electrons are localized between the atoms and not free to move and carry charge.

3. The process of bone formation and breakdown is called:

A. Ossification
B. Resorption
C. Remodeling
D. All of the above

Correct answer: C

Rationale: The correct answer is C: 'Remodeling.' Bone remodeling is the continuous process of bone formation (ossification) and breakdown (resorption). Ossification refers to the formation of bone tissue, while resorption is the breakdown and removal of old bone tissue. The term 'remodeling' encompasses both of these processes, making it the most appropriate choice. While ossification and resorption are part of bone remodeling, they do not cover the entire process on their own, hence 'All of the above' is incorrect.

4. Where does most of the chemical digestion and absorption of nutrients occur?

A. Mouth
B. Stomach
C. Small intestine
D. Large intestine

Correct answer: C

Rationale: Rationale: The small intestine is where most of the chemical digestion and absorption of nutrients occur in the digestive system. This is because the small intestine is lined with villi and microvilli, which increase the surface area available for absorption. Enzymes secreted by the pancreas and bile from the liver aid in breaking down food into smaller molecules that can be absorbed through the intestinal wall into the bloodstream. The stomach primarily functions in the mechanical breakdown of food and the initial stages of protein digestion, while the large intestine is mainly responsible for absorbing water and electrolytes from the remaining indigestible food particles. The mouth is involved in the initial mechanical breakdown of food through chewing and some chemical digestion of carbohydrates by salivary enzymes, but the majority of nutrient absorption occurs in the small intestine.

5. The concept of punctuated equilibrium suggests that:

A. Evolution occurs gradually through the continuous accumulation of small changes over long periods.
B. Evolution is characterized by long periods of relative stasis punctuated by rapid bursts of evolutionary change.
C. The fossil record is a complete and accurate representation of all past life forms.
D. Natural selection primarily favors extreme phenotypes within a population.

Correct answer: B

Rationale: Rationale: A) Evolution occurs gradually through the continuous accumulation of small changes over long periods - This statement describes the gradualism model of evolution, not punctuated equilibrium. Punctuated equilibrium suggests that evolution is characterized by long periods of little to no change (stasis) followed by relatively rapid bursts of evolutionary change. B) Evolution is characterized by long periods of relative stasis punctuated by rapid bursts of evolutionary change - This statement accurately describes the concept of punctuated equilibrium proposed by Stephen Jay Gould and Niles Eldredge. It suggests that species remain relatively unchanged for long periods of time, interrupted by sudden bursts of rapid evolution. C) The fossil record is a complete and accurate representation of all past life forms - This statement is incorrect as the fossil record is incomplete and biased towards certain types of organisms and environments. It does not provide a complete and accur