The question is incomplete, the complete question is;
The lightest particle among the following is:
• Electron •Proton • Neutron • Alpha
Answer:
Electron
Explanation:
There three basic subatomic particles are electrons, protons and neutrons. Both protons and neutrons are found in the nuclear and both contribute towards the mass of the atom. The alpha particle has the same mass as the helium nucleus.
However, the electrons are found in orbiit and have a negligible mass compared to the mass of the protons and neutrons. The mass of the electron is about 9.11 × 10^-31 Kg. This makes it the lightest of all the particles listed among the options.
Answer: The correct option is 4.
Explanation: All the options will undergo some type of radioactive decay processes. There are 3 decay processes:
1) Alpha decay: It is a decay process in which alpha particle is released which has has a mass number of 4 and a charge of +2.

2) Beta-minus decay: It is a decay in which a beta particle is released. The beta particle released has a mass number of 0 and a charge of (-1).

3) Beta-plus decay: It is a decay process in which a positron is released. The positron released has a mass number of 0 and has a charge of +1.

For the given options:
Option 1: This nuclei will undergo beta-plus decay process to form 

Option 2: This nuclei will undergo beta-minus decay process to form 

Option 3: This nuclei will undergo a beta minus decay process to form 

Option 4: This nuclei will undergo an alpha decay process to form 

Hence, the correct option is 4.
For each molecule of glucose produced: 6 water water molecules are oxidized, and come to be the supply of electrons for carbon dioxide reduction. 6 molecules of carbon dioxide are required, one for every carbon atom in glucose. 6 molecules of oxygen are produced as a with the aid of made from water oxidation.
<h2>Entropy of the system decreases when methane gas and oxygen gas combust to form carbon dioxide and water.</h2>
Explanation:
- Salt crystals when dissolved in water the bond between the molecules of crystals are broken down increasing the movement between the atoms hence entropy is increased.
- When air escapes from a hole in the balloon,the entropy increases as the air present inside the balloon occupies small volume as compared to outside.
- Ice when melts at room temperature its entropy increases because the molecule in the ice are closely packed hence less movement between the molecules.
- When water boils the kinetic energy increases or themovement between the atoms increases which increases the entropy.
Hence, the option (a), (b), (c), and (d) are not suitable to the statement that "the entropy of the system decreases".
- During combustion of methane gas there is release of carbon dioxide gas and water .Here, entropy decreases due to the formation of water which is due to overall decrease in the kinetic energy of the system.
If bubbles aren't a for sure way of knowing a chemical reaction I don't know what is. But being for real, it is a chemical change because the bubbles are releasing carbon dioxide meaning it turned into a product from a reaction with outside forces.