The right answer is 2.
The number of protons contained in a nucleus (called an atomic number) is characteristic of a chemical element. For a given atomic number, the number of neutrons defines different "types" of this element: isotopes. The variation of the number of protons of the nucleus of an atom, during a nuclear reaction for example, causes a change of the element studied.
Answer:
is reduced in the reaction
Explanation:
The given reaction is

The oxidation number of
is changed from 

And The oxidation number of
is changed from 

Hence,
is oxidized and
is reduced
Answer: Physical properties
Explanation: Can be measured without changing a substance's chemical identity.
Answer:
The scientist is observing an intensive property of a superconductor.
Explanation:
An intensive property is a bulk property of matter. This means that an intensive property does not depend on the amount of substance present in the material under study. Typical examples of intensive properties include; conductivity, resistivity, density, hardness, etc.
An extensive property is a property that depends on the amount of substance present in a sample. Extensive properties depend on the quantity of matter present in the sample under study. Examples of extensive properties include, mass and volume.
Resistance of a superconducting material has nothing to do with the amount of the material present hence it is an intensive property of the superconductor.
To solve this problem, we must be given first the density
of air at 20 degrees Celsius. Looking up online, this is equal to:
density air (20C) = 0.0012041 g/mL
so that the volume is:
volume balloon = 0.57 g / (0.0012041
g/mL)
<span>volume balloon = 473.38 mL</span>