balance the chemical equation c4h10 o2 co2 h2o what is the coefficient for oxygen

ATI TEAS 7

ATI TEAS 7 science review

1. Balance the chemical equation: C4H10 + O2 → CO2 + H2O. What is the coefficient for oxygen?

A. 5
B. 6
C. 7
D. 8

Correct answer: B

Rationale: To balance the chemical equation, we need to ensure that the number of each type of atom is the same on both sides of the equation. In this case, there are 10 oxygen atoms on the right side (5 in CO2 and 5 in H2O). To balance this, we need to add a coefficient of 6 in front of O2 on the left side, resulting in 6 O2 molecules. This change will give us a total of 12 oxygen atoms on both sides, making the equation balanced. Choice A (5) is incorrect because it does not account for all the oxygen atoms present in the products. Choices C (7) and D (8) are incorrect as they would result in an imbalance in the number of oxygen atoms on both sides of the equation.

2. Which organ produces bile to aid in digestion?

A. Pancreas
B. Liver
C. Gallbladder
D. Stomach

Correct answer: B

Rationale: The correct answer is B: Liver. The liver produces bile, which is stored in the gallbladder and released into the small intestine to aid in the digestion and absorption of fats. The pancreas secretes digestive enzymes, not bile. The gallbladder stores bile but does not produce it. The stomach produces gastric juices, not bile, to aid in digestion.

3. Which of the following describes a responsibility of the integumentary system?

A. Distributing vital substances, such as nutrients, throughout the body.
B. Blocking pathogens that cause disease.
C. Sending leaked fluids from the cardiovascular system back to the blood vessels.
D. Storing bodily hormones that influence gender traits.

Correct answer: B

Rationale: The correct responsibility of the integumentary system is to act as a barrier that blocks pathogens from entering the body, thus helping to prevent diseases and infections. This function serves as the first line of defense for the body against external threats. Choices A, C, and D are incorrect. Choice A is a function of the circulatory system, not the integumentary system. Choice C relates to the lymphatic system, not the integumentary system. Choice D involves the endocrine system, not the integumentary system.

4. What are the differences between RNA and DNA?

A. Both have the same structure and function.
B. RNA is single-stranded, while DNA is double-stranded.
C. RNA contains ribose sugar, while DNA contains deoxyribose sugar.
D. RNA has adenine and guanine, while DNA has thymine and cytosine.

Correct answer: B

Rationale: A) This statement is incorrect. RNA and DNA have different structures and functions. RNA is involved in protein synthesis and other cellular processes, while DNA stores genetic information. B) This statement is correct. RNA is typically single-stranded, while DNA is double-stranded, forming a double helix structure. C) This statement is correct. RNA contains ribose sugar in its backbone, while DNA contains deoxyribose sugar. D) This statement is incorrect. RNA contains adenine, guanine, cytosine, and uracil, while DNA contains adenine, guanine, cytosine, and thymine. Choice B is the correct answer as it accurately describes one of the key differences between RNA and DNA, emphasizing their structural disparity in terms of single-strandedness for RNA and double-strandedness for DNA. Choices A, C, and D contain inaccuracies regarding the structural and compositional distinctions between RNA and DNA, making them incorrect choices.

5. Which of the following is an example of a ball-and-socket joint?

A. Knee
B. Hip
C. Elbow
D. Wrist

Correct answer: B

Rationale: The correct answer is B, Hip. The hip joint is a ball-and-socket joint, characterized by the spherical head of one bone (femur) fitting into the cup-like socket of another bone (pelvis). This structure allows for a wide range of motion in multiple directions, such as flexion, extension, abduction, adduction, and rotation. Choices A, C, and D are incorrect as the knee, elbow, and wrist joints are not ball-and-socket joints. The knee is a hinge joint, allowing flexion and extension movements. The elbow is a hinge joint that allows flexion and extension, while the wrist is a condyloid joint permitting flexion, extension, abduction, adduction, and circumduction movements.