Answer/Explanation:
Methanol has a molecular weight (32.04 g/mol), low-boiling point and because of its low boiling point, methanol readily evaporates at room temperature.
Under these specified non-standard conditions, the partial pressure of methanol is lower than its vapor pressure and this explains the reason for the spontaneous evaporation exhibited by methanol.
Im a bit torn here, lets look at the definitions of physical and chemical changes:
physical change changes only the phase/state of a substance, but not what the substance is
chemical change is a chemical reaction where a new substance is formed and energy is given off or absorbed.
(it just started raining and it smells really nice out my window)
clearly, this cannot be just a physical reaction. i think i would be inclined to pick B. but C. could have merit as an answer too. sorry for the ambiguity x
When an electron quickly occupies an strength state increased than its ground state, it is in an excited state. An electron can end up excited if it is given greater energy, such as if it absorbs a photon, or packet of light, or collides with a close by atom or particle.
Answer: option D - The total number of nucleons changes.
Explanation:
Nuclear Reaction is best described as a process such as the fission of an atomic nucleus, or the fusion of one or more atomic nuclei and / or subatomic particles in which the NUMBER of PROTONS and / or NEUTRONS in a nucleus CHANGES; the reaction products may contain a different element or a different isotope of the same element.
Note that the NUCLEONS refers to ONE of the subatomic particles of the atomic nucleus, i.e. a PROTON or a NEUTRON.
So, in a Nuclear reaction, the total number of nucleons changes.