Question 1

Chromium is an ultratrace metal in the human body. The typical concentration is 5.0 mg in 70.0 kg of body mass. This concentration can be expressed as ________

Accepted Answer

A) 0.071 ppm or 71 pp 
B) 71 ppm or 0.071 ppb. 
C) 14 ppm or 14,000 ppb. 
D) 0.71 ppm or 710 ppb. 
E) 5.0 ppm or 500 ppb.

Question 2

Hearing aid batteries utilize a zinc/air electrochemical cell. The reduction half-reactions and standard reduction potentials for this cell are given below. Identify the oxidizing agent and the reducing agent in this cell.  F1F1F1S1F1F1F101.249 V  F1F1F1S1F1F1F100.401 V

Accepted Answer

The answer of Hearing aid batteries utilize a zinc/air electrochemical...

Question 3

Chromium is an ultratrace metal in the human body with a typical concentration of 5.0 mg in 75 kg of body mass. What is this concentration in units of parts per billion (ppb)?

Accepted Answer

A) 6.7 F1F1F1S1F1F1F10 107 ppb 
B) 6.7 F1F1F1S1F1F1F10 104 ppb 
C) 67 ppb 
D) 0.067 ppb 
E) 0.67 ppb

Question 4

The concentration of chloride in the human body is approximately 19 mg/g of body mass. What is this concentration in ppb (parts per billion)?

Accepted Answer

A) 1.9 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F102 ppb 
B) 1.9 F1F1F1S1F1F1F10 107 ppb 
C) 1.9 F1F1F1S1F1F1F10 104 ppb 
D) 1,900 ppb 
E) 190 ppb

Question 5

Iodine's role is very specific. It is incorporated into a hormone, ________, that regulates energy production and use.

Accepted Answer

A) melatonin 
B) thyroxine 
C) dopamine 
D) insulin 
E) iodocin

Question 6

Barium is a nonessential element in the human body, but some organisms build exoskeletons using barium sulfate, which has a Ksp of 1.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1010 at 25F1F1F1S1F1F1F10C. What is the mass of barium in 1.0 L of a saturated solution of barium sulfate at 25F1F1F1S1F1F1F10C?

Accepted Answer

A) 4.1 F1F1F1S1F1F1F10g 
B) 1.4 mg 
C) 3.7 mg 
D) 7.3 F1F1F1S1F1F1F10g 
E) 15 ng

Question 7

Adding fluoride ions to toothpaste and drinking water to prevent tooth decay is effective because fluoride ________

Accepted Answer

A) kills decay-producing bacteria. 
B) produces stronger teeth. 
C) reduces the solubility of tooth enamel at low pH. 
D) reduces the solubility of tooth enamel at high pH. 
E) prevents halitosis.

Question 8

Plants convert nitrogen into ammonia. This biological nitrogen fixation is affected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is  What is the stoichiometric coefficient for HF1F1F1S1F1F1F10 in the balanced reaction equation?

Accepted Answer

A) 1 
B) 2 
C) 4 
D) 6 
E) 8

Question 9

Thallium-201 is used in cardiac imaging. It decays by electron capture. What isotope is produced when thallium-201 captures an electron?

Accepted Answer

A) thallium-202 
B) lead-201 
C) lead-202 
D) mercury-201 
E) mercury-202

Question 10

Nickel-cadmium batteries thrown into landfills can introduce cadmium ions into the groundwater. Cadmium ions can replace ________ in bones, which can weaken them.

Accepted Answer

A) NaF1F1F1S1F1F1F10 
B) KF1F1F1S1F1F1F10 
C) Zn2F1F1F1S1F1F1F10 
D) Ca2F1F1F1S1F1F1F10 
E) Mg2F1F1F1S1F1F1F10

Question 11

Which anion is most abundant in the human body?

Accepted Answer

A) IF1F1F1S1F1F1F10 
B) Br F1F1F1S1F1F1F10 
C) CO32F1F1F1S1F1F1F10 
D) ClF1F1F1S1F1F1F10 
E) NO3F1F1F1S1F1F1F10

Question 12

Which element, by the number of atoms, is most abundant in the human body?

Accepted Answer

A) carbon 
B) oxygen 
C) hydrogen 
D) nitrogen 
E) calcium

Question 13

What is the dominant role played by iodine in the body?

Accepted Answer

A) maintains osmotic pressure 
B) transmits nerve impulses 
C) forms structural materials 
D) a key component in enzymes 
E) important in the function of the thyroid gland

Question 14

The essential elements found in the human body are classified as major, trace, and ultratrace based on their concentration levels. What are the concentration ranges that define each of these classifications?

Accepted Answer

The answer of The essential elements found in the human...

Question 15

Enzymes in plants convert nitrate into ammonia. The unbalanced half-reaction equation is given below. What is the change in oxidation number of nitrogen in this reaction?

Accepted Answer

The answer of Enzymes in plants convert nitrate into ammonia....

Question 16

Plants convert nitrogen into ammonia. This biological nitrogen fixation is effected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is  What is the change in the oxidation number of nitrogen in this reaction?

Accepted Answer

A) (F1F1F1S1F1F1F101) 
B) (F1F1F1S1F1F1F103) 
C) (F1F1F1S1F1F1F103) 
D) (F1F1F1S1F1F1F102) 
E) (F1F1F1S1F1F1F101)

Question 17

The release of radioactive cesium-137 into the environment by the nuclear accident at Chernobyl produced a health hazard because cesium ions can substitute for ________ in plants, making them unsafe for human consumption.

Accepted Answer

A) Mg2F1F1F1S1F1F1F10 
B) KF1F1F1S1F1F1F10 
C) Ca2F1F1F1S1F1F1F10 
D) LiF1F1F1S1F1F1F10 
E) HF1F1F1S1F1F1F10

Question 18

Tooth enamel is composed of the mineral hydroxyapatite. It is essentially insoluble in water with Ksp F1F1F1S1F1F1F10 2.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1059, but it reacts with weak acids in the mouth as described by one of the reaction equations below. You can determine the equilibrium constant, K, for this reaction from Ksp and Kw (the equilibrium constant for water autoionization, Kw F1F1F1S1F1F1F10 1.0 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1014). What is the value of K?

Accepted Answer

A) 2.3 F1F1F1S1F1F1F10 10 F1F1F1S1F1F1F1073 
B) 4.3 F1F1F1S1F1F1F10 10 45 
C) 2.3 F1F1F1S1F1F1F10 10 F1F1F1S1F1F1F1045 
D) 1.1 F1F1F1S1F1F1F10 10 F1F1F1S1F1F1F1014 
E) 9.9 F1F1F1S1F1F1F10 10 F1F1F1S1F1F1F1015

Question 19

What is the dominant role played by calcium in the body?

Accepted Answer

A) maintains osmotic pressure 
B) transmits nerve impulses 
C) forms structural materials 
D) a key component in enzymes 
E) important in the function of the thyroid gland

Question 20

Plants convert nitrogen into ammonia. This biological nitrogen fixation is effected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is  What is the stoichiometric coefficient for the electrons in the balanced reaction equation?

Accepted Answer

A) 1 
B) 2 
C) 4 
D) 6 
E) 8

Exam 21: The Main Group Elements: Life and the Periodic Table

Chromium is an ultratrace metal in the human body. The typical concentration is 5.0 mg in 70.0 kg of body mass. This concentration can be expressed as ________

Hearing aid batteries utilize a zinc/air electrochemical cell. The reduction half-reactions and standard reduction potentials for this cell are given below. Identify the oxidizing agent and the reducing agent in this cell. 1.249 V 0.401 V

Chromium is an ultratrace metal in the human body with a typical concentration of 5.0 mg in 75 kg of body mass. What is this concentration in units of parts per billion (ppb) ?

The concentration of chloride in the human body is approximately 19 mg/g of body mass. What is this concentration in ppb (parts per billion) ?

Iodine's role is very specific. It is incorporated into a hormone, ________, that regulates energy production and use.

Barium is a nonessential element in the human body, but some organisms build exoskeletons using barium sulfate, which has a K_sp of 1.1  10^¹⁰ at 25C. What is the mass of barium in 1.0 L of a saturated solution of barium sulfate at 25C?

Adding fluoride ions to toothpaste and drinking water to prevent tooth decay is effective because fluoride ________

Plants convert nitrogen into ammonia. This biological nitrogen fixation is affected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is What is the stoichiometric coefficient for H^ in the balanced reaction equation?

Thallium-201 is used in cardiac imaging. It decays by electron capture. What isotope is produced when thallium-201 captures an electron?

Nickel-cadmium batteries thrown into landfills can introduce cadmium ions into the groundwater. Cadmium ions can replace ________ in bones, which can weaken them.

Which anion is most abundant in the human body?

Which element, by the number of atoms, is most abundant in the human body?

What is the dominant role played by iodine in the body?

The essential elements found in the human body are classified as major, trace, and ultratrace based on their concentration levels. What are the concentration ranges that define each of these classifications?

Enzymes in plants convert nitrate into ammonia. The unbalanced half-reaction equation is given below. What is the change in oxidation number of nitrogen in this reaction?

Plants convert nitrogen into ammonia. This biological nitrogen fixation is effected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is What is the change in the oxidation number of nitrogen in this reaction?

The release of radioactive cesium-137 into the environment by the nuclear accident at Chernobyl produced a health hazard because cesium ions can substitute for ________ in plants, making them unsafe for human consumption.

What is the dominant role played by calcium in the body?

Plants convert nitrogen into ammonia. This biological nitrogen fixation is effected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is What is the stoichiometric coefficient for the electrons in the balanced reaction equation?

Exam 21: The Main Group Elements: Life and the Periodic Table

Chromium is an ultratrace metal in the human body. The typical concentration is 5.0 mg in 70.0 kg of body mass. This concentration can be expressed as ________

Hearing aid batteries utilize a zinc/air electrochemical cell. The reduction half-reactions and standard reduction potentials for this cell are given below. Identify the oxidizing agent and the reducing agent in this cell. 1.249 V 0.401 V

Chromium is an ultratrace metal in the human body with a typical concentration of 5.0 mg in 75 kg of body mass. What is this concentration in units of parts per billion (ppb) ?

The concentration of chloride in the human body is approximately 19 mg/g of body mass. What is this concentration in ppb (parts per billion) ?

Iodine's role is very specific. It is incorporated into a hormone, ________, that regulates energy production and use.

Barium is a nonessential element in the human body, but some organisms build exoskeletons using barium sulfate, which has a Ksp of 1.1  1010 at 25C. What is the mass of barium in 1.0 L of a saturated solution of barium sulfate at 25C?

Adding fluoride ions to toothpaste and drinking water to prevent tooth decay is effective because fluoride ________

Plants convert nitrogen into ammonia. This biological nitrogen fixation is affected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is What is the stoichiometric coefficient for H in the balanced reaction equation?

Thallium-201 is used in cardiac imaging. It decays by electron capture. What isotope is produced when thallium-201 captures an electron?

Nickel-cadmium batteries thrown into landfills can introduce cadmium ions into the groundwater. Cadmium ions can replace ________ in bones, which can weaken them.

Which anion is most abundant in the human body?

Which element, by the number of atoms, is most abundant in the human body?

What is the dominant role played by iodine in the body?

The essential elements found in the human body are classified as major, trace, and ultratrace based on their concentration levels. What are the concentration ranges that define each of these classifications?

Enzymes in plants convert nitrate into ammonia. The unbalanced half-reaction equation is given below. What is the change in oxidation number of nitrogen in this reaction?

Plants convert nitrogen into ammonia. This biological nitrogen fixation is effected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is What is the change in the oxidation number of nitrogen in this reaction?

The release of radioactive cesium-137 into the environment by the nuclear accident at Chernobyl produced a health hazard because cesium ions can substitute for ________ in plants, making them unsafe for human consumption.

What is the dominant role played by calcium in the body?

Plants convert nitrogen into ammonia. This biological nitrogen fixation is effected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is What is the stoichiometric coefficient for the electrons in the balanced reaction equation?

Barium is a nonessential element in the human body, but some organisms build exoskeletons using barium sulfate, which has a K_sp of 1.1  10^¹⁰ at 25C. What is the mass of barium in 1.0 L of a saturated solution of barium sulfate at 25C?

Plants convert nitrogen into ammonia. This biological nitrogen fixation is affected by enzymes called nitrogenases. The enzymes assist in the transfer of electrons. The unbalanced reaction equation is What is the stoichiometric coefficient for H^ in the balanced reaction equation?