How many times stronger is the hydrogen-ion concentration of a pH 4 solution as compared with a pH 9 solution?
A. 0.00001
B. 5
C. 100,000
D. 50
The correct answer is c. 100,000. The pH scale is a logarithmic scale, which means that each change of one pH unit represents a tenfold change in the hydrogen-ion concentration. A pH 4 solution has a hydrogen-ion concentration that is 10^5 (or 100,000) times greater than that of a pH 9 solution.
a. 0.00001 is the hydrogen-ion concentration of a pH 9 solution as compared with a pH 4 solution.
b. 5 is the difference in pH units between a pH 4 solution and a pH 9 solution.
d. 50 is not the correct answer.
Therefore, the Correct Answer is C.
More Questions on TEAS 7 Science
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Q #1: Lipids absorbed in the small intestine will first enter which of the following structures?
A. Veins
B. Arteries
C. Lacteal vessels
D. Interstitial spaces
Answer Explanation
The correct answer is c. Lacteal vessels. Lipids absorbed in the small intestine will first enter lacteal vessels, which are small lymphatic vessels located in the villi of the small intestine. These vessels transport the absorbed lipids to the lymphatic system, where they eventually enter the bloodstream.
a. Veins and b. Arteries are blood vessels that transport blood throughout the body. Lipids absorbed in the small intestine do not directly enter these vessels.
d. Interstitial spaces are spaces between cells and tissues that contain interstitial fluid. Lipids absorbed in the small intestine do not directly enter these spaces.
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Q #2: Which of the following structures is an exocrine gland?
A. Pineal gland
B. Parathyroid gland
C. Parotid gland
D. Pituitary gland
Answer Explanation
The parotid gland is an exocrine gland that secretes saliva into the mouth. Exocrine glands secrete their products into ducts that carry the secretions to the body's surface or into body cavities. The other options are endocrine glands, which secrete hormones directly into the bloodstream. The pineal gland secretes melatonin, the parathyroid glands secrete parathyroid hormone, and the pituitary gland secretes several hormones that regulate various bodily functions.
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Q #3: A study found two processes, Process A and Process B, to be correlated. Which of the following is true for these processes?
A. The study indicates that Process A causes Process B.
B. The study cannot indicate whether Process A and B have a positive relationship.
C. The study does not indicate a causal relationship between the processes.
D. The study cannot indicate whether Process A and B have a negative relationship.
Answer Explanation
The correct answer is c.
The study does not indicate a causal relationship between the processes. A correlation between two processes means that there is a statistical relationship between them, but it does not necessarily imply causation. In other words, just because two processes are correlated does not mean that one causes the other.
b.The study does not indicate that Process A causes Process B.
b.The study can indicate whether Process A and B have a positive relationship if the correlation is positive.
d. The study can indicate whether Process A and B have a negative relationship if the correlation is negative.
