知到答案Basic Chemistry 基础化学智慧树答案_2022年

天津大学

第二章

A certain mass of carbon reacts with 13.6 g of oxygen to form carbon monoxide. __________ grams of oxygen would react with that same mass of carbon to form carbon dioxide, according to the law of multiple proportions?
136
27.2
6.8
25.6
答案:27.2
Which statement below correctly describes the responses of alpha, beta, and gamma radiation to an electric field?
Both alpha and gamma are deflected in the same direction, while beta shows no response
Only alpha is deflected, while beta and gamma show no response
Both alpha and beta are deflected in the same direction, while gamma shows no response
Alpha and beta are deflected in opposite directions, while gamma shows no response
答案:Alpha and beta are deflected in opposite directions, while gamma shows no response
__________ and __________ reside in the atomic nucleus.
none of the above
Neutrons, only neutrons
Protons, neutrons
Protons, electrons
答案:Protons, neutrons
Which one of the following is not true concerning cathode rays?
They impart a negative charge to metals exposed to them
The characteristics of cathode rays depend on the material from which they are emitted
They travel in straight lines in the absence of electric or magnetic fields
They originate from the negative electrode
答案:The characteristics of cathode rays depend on the material from which they are emitted
The charge on an electron was determined in the __________.
Rutherford gold foil experiment
Millikan oil drop experiment
atomic theory of matter
Dalton atomic theory
答案:Millikan oil drop experiment
In the Rutherford nuclear-atom model, __________.
the heavy subatomic particles, protons and neutrons, reside in the nucleus
the three principal subatomic particles (protons, neutrons, and electrons) all have essentially the same mass
mass is spread essentially uniformly throughout the atom
the three principal subatomic particles (protons, neutrons, and electrons) all have essentially the same mass and mass is spread essentially uniformly throughout the atom
答案:the heavy subatomic particles, protons and neutrons, reside in the nucleus
All atoms of a given element have the same __________.
number of electrons and neutrons
number of neutrons
density
number of protons
答案:number of protons
An atom of the most common isotope of gold, 197Au, has __________ protons, __________ neutrons, and __________ electrons.
197, 79, 118
79, 118, 118
79, 118, 79
118, 79, 39
答案:79, 118, 79
Which combination of protons, neutrons, and electrons is correct for the isotope copper-63, ?
34 p+ , 29 n°, 34 e−
29 p+ , 34 n°, 29 e−
34 p+ , 34 n°, 29 e−
63 p+ , 29 n°, 63 e−
答案:29 p+ , 34 n°, 29 e−
Isotopes are atoms that have the same number of __________ but differing number of __________.
protons, electrons
protons, neutrons
electrons, protons
neutrons, protons
答案:protons, neutrons