The answer is (3) HClO. In the Cl2, chlorine has an oxidation number of zero. In HCl, the oxidation number is -1. In HClO2, the oxidation number is +3. In HClO, it is +1. You can calculate this by using O with oxidation number of -2 and H with +1.
The correct answer is this: THE NUCLEUS OF AN ATOM SPLITS INTO FRAGMENTS, RELEASING A LARGE AMOUNT OF ENERGY.
Nuclear fission is the process in which the nucleus of a radioactive element split into two different nucleic of smaller sizes of different elements with a large release of energy. Nuclear fission process is usually used to provide energy for electricity generation.
Answer:

This is a double displacement reaction, C goes with Cl in the products side and O2 goes with H. All that is left is to balance the equation, making sure each side has equal amounts of atoms.
Answer:
The flame will burn out
Explanation:
The oxygen will be kept out of the jar, without oxygen the flame cannot last long. The flame will eventually burn out. Nitrogen gas has no role to play in the burning. Nitrogen slows down the burning rate.
The boiling point of oxygen is higher than nitrogen's boiling
The reason the boiling point of O2 is higher is not because of increased van der Waals interactions, but simple physics. The mass of a molecule of O2 is greater than that of a molecule of N2, so the molecule of O2 traveling at a speed sufficient to break out of the liquid phase has a greater kinetic energy than an analogous N2 molecule.
The net effect is that more energy must be distributed throughout a sample of O2 to achieve a given vapor pressure (in this case equal to atmospheric pressure) than for a sample of N2. More energy means greater temperature.