Chem Study
An example of potential energy is A) a coiled spring. B) running water. C) tree branches blowing in the breeze. D) a moving elevator. E) electrical energy.
Points Earned: 1.0/1.0 The correct answer is A.
The definition of potential energy is an inactive type of energy that is stored for future use. All of these answers describe active energy, for example, running water is very active but can generate other types of energy.
Which one of the following substances will float in gasoline, which has a density of 0.66 g/mL? A) table salt (density = 2.16 g/mL. B) aluminum (density = 2.70 g/mL. C) mercury (density = 13.6 g/mL. D) balsa wood (density = 0.16 g/mL. E) sugar (density = 1.59 g/mL.
The correct answer is D. According to page 43, objects float that are less dense than the liquid it’s in. All of the answers have density greater than .66g/ml except balsa wood which equals to .16 g/ml.
A radioactive sample was measured as having a mass of 160 mg. Six hours later, the sample’s mass was measured at 40 mg. What is the half-life of the sample?
A) six hours
B) one and one-half hours
C) twelve hours
D) nine hours
E) three hours
Points Earned: 1.0/1.0
The correct answer is E, three hours. The definition of Half-life according to page book is the length of time it takes for one-half of a radioactive sample to decay. 160mg divided by 2 equals 80, (which is the half- life of the sample.) If you divide the six hours it took the sample to reach 40mg by two. The answer will be three hours.
a) Is incorrect because it equal 2 half-lives.
15.
The smallest particle of an element that retains the characteristics of the element is a(n)
A) atom.
B) electron.
C) nucleus.
D) neutron.
E) proton.
The correct answer is A), atom. According to page 105 an atom retains the characteristic of that element.
b) Describes the negative charge of a particle. Even though it has no mass it is not considered the characteristic of that element
c)
Points Earned: 1.0/1.0 The correct answer is A.
The definition of potential energy is an inactive type of energy that is stored for future use. All of these answers describe active energy, for example, running water is very active but can generate other types of energy.
Which one of the following substances will float in gasoline, which has a density of 0.66 g/mL? A) table salt (density = 2.16 g/mL. B) aluminum (density = 2.70 g/mL. C) mercury (density = 13.6 g/mL. D) balsa wood (density = 0.16 g/mL. E) sugar (density = 1.59 g/mL.
The correct answer is D. According to page 43, objects float that are less dense than the liquid it’s in. All of the answers have density greater than .66g/ml except balsa wood which equals to .16 g/ml.
A radioactive sample was measured as having a mass of 160 mg. Six hours later, the sample’s mass was measured at 40 mg. What is the half-life of the sample?
A) six hours
B) one and one-half hours
C) twelve hours
D) nine hours
E) three hours
Points Earned: 1.0/1.0
The correct answer is E, three hours. The definition of Half-life according to page book is the length of time it takes for one-half of a radioactive sample to decay. 160mg divided by 2 equals 80, (which is the half- life of the sample.) If you divide the six hours it took the sample to reach 40mg by two. The answer will be three hours.
a) Is incorrect because it equal 2 half-lives.
15.
The smallest particle of an element that retains the characteristics of the element is a(n)
A) atom.
B) electron.
C) nucleus.
D) neutron.
E) proton.
The correct answer is A), atom. According to page 105 an atom retains the characteristic of that element.
b) Describes the negative charge of a particle. Even though it has no mass it is not considered the characteristic of that element
c)