how many grams of solid caco are needed to make 600 ml of a 35 m solution the atomic masses for the elements are as follows ca 07 gmol c 01 gmol o

ATI TEAS 7

ATI TEAS Science Questions

1. How many grams of solid CaCO3 are needed to make 600 mL of a 35 M solution? The atomic masses for the elements are as follows: Ca = 40.1 g/mol; C = 12.01 g/mol; O = 16.00 g/mol.

A. 18.3 g
B. 19.7 g
C. 21.0 g
D. 24.2 g

Correct answer: B

Rationale: 1. First, calculate the molar mass of CaCO3 by adding the atomic masses of Ca, C, and 3 O atoms: 40.1 + 12.01 + (3 * 16.00) = 100.13 g/mol. 2. Calculate the number of moles in 600 mL of a 35 M solution: 600 mL * 35 mol/L = 21,000 mmol. 3. Convert moles to grams using the molar mass of CaCO3: 21,000 mmol * (100.13 g/mol / 1000 mmol/mol) = 2,102.73 g. 4. Therefore, you would need 19.7 g of solid CaCO3 to make 600 mL of a 35 M solution.

2. What happens during expiration?

A. The diaphragm contracts and the thoracic cavity expands.
B. The diaphragm relaxes and the thoracic cavity contracts.
C. The thoracic cavity expands, increasing pressure.
D. The diaphragm relaxes and moves upward.

Correct answer: B

Rationale: The correct answer is B. During expiration, the diaphragm relaxes, causing the thoracic cavity to contract. As the thoracic cavity decreases in size, the pressure inside the lungs increases, leading to air flowing out of the lungs. This process helps to expel carbon dioxide-rich air from the body. Choices A, C, and D are incorrect. In choice A, the diaphragm contracting and the thoracic cavity expanding describes inspiration, not expiration. Choice C is incorrect because during expiration, the thoracic cavity actually decreases in size. Choice D is incorrect as the diaphragm moving upward is not a typical movement associated with expiration.

3. Which condition can lead to blood clots and stroke?

A. Aneurysm
B. Arrhythmia
C. Asthma
D. Hypertension

Correct answer: D

Rationale: Hypertension is the correct answer. Hypertension can cause damage to blood vessels, increasing the risk of blood clots forming, which can potentially lead to a stroke. Aneurysm is a localized, abnormal dilation of a blood vessel that can lead to complications but does not directly cause blood clots and strokes. Arrhythmia refers to irregular heart rhythms and is not directly linked to the formation of blood clots. Asthma is a chronic respiratory condition and does not typically lead to blood clots and strokes.

4. Which of the following glands is NOT directly controlled by the pituitary gland?

A. Thyroid gland
B. Adrenal glands
C. Pancreas (Islets of Langerhans)
D. Parathyroid glands

Correct answer: C

Rationale: The pituitary gland, known as the master gland, regulates various endocrine glands by releasing specific hormones. The thyroid gland, adrenal glands, and parathyroid glands are directly controlled by the pituitary gland through hormones like thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), and parathyroid hormone (PTH) respectively. However, the pancreas, particularly the Islets of Langerhans, is not directly influenced by the pituitary gland. The pancreas is mainly governed by blood glucose levels and hormones such as insulin and glucagon, which play a crucial role in regulating blood sugar levels and metabolism. Therefore, the correct answer is C. Choice A, the thyroid gland, is controlled by the pituitary gland through TSH. Choice B, the adrenal glands, are regulated by the pituitary gland via ACTH. Choice D, the parathyroid glands, are under the direct control of the pituitary gland through PTH.

5. How are sister chromatids distinguished from homologous chromosomes in meiosis I?

A. Sister chromatids share the same centromere, while homologous chromosomes have different centromeres.
B. Sister chromatids have identical DNA sequences, while homologous chromosomes have slightly different sequences due to crossing over.
C. Sister chromatids repel each other, while homologous chromosomes attract each other during synapsis.
D. Sister chromatids separate during anaphase I, while homologous chromosomes separate during anaphase II.

Correct answer: B

Rationale: In meiosis I, sister chromatids are exact copies of each other, containing identical DNA sequences. On the other hand, homologous chromosomes are pairs of chromosomes, with one inherited from each parent, and they can have different versions of genes due to genetic recombination during crossing over in prophase I. Choice A is incorrect because homologous chromosomes naturally have different centromeres. Choice C is incorrect as sister chromatids and homologous chromosomes do not exhibit repulsion or attraction during synapsis. Choice D is incorrect as sister chromatids separate during anaphase II, not anaphase I, while homologous chromosomes separate during anaphase I.