Answer: (3) They have different masses and the same charges.
Explanation:
Atoms are mainly composed of three main types of particles (in fact there are more particles that are smaller and make up these main particles): electrons, protons and neutrons.
In the specific case of <u>electrons</u> and <u>protons</u>, <u>both have the same charge, but electrons have the opposite sign</u>. This means a proton has an electric charge of +1 and an electron has an electric charge of −1.
On the other hand, <u>protons have more mass than electrons.</u> In fact, thetex]mass of an electron is about approximately 
the mass of a proton, this means these negative charged particles contribute almost nothing to the total mass of an atom (unlike protons, which together with neutrons, make up virtually all of the mass of an atom).
However, each atom that is electrically neutral has the same quantity of electrons as protons.
Combustion can be defined as the reaction of a compound with oxygen. The enthalpy of combustion of octane is 
for 
.
<h3>What is the enthalpy of reaction?</h3>
The enthalpy of reaction is the amount of heat energy absorbed or lost by the molecules in the chemical reaction.
The enthalpy of combustion is the amount of heat energy released by the compound in the reaction with oxygen.
The reaction in which heat is liberated with the reaction of a compound with oxygen has an enthalpy of combustion, equivalent to the enthalpy of reaction.
The combustion of octane can be given as:
Thus, the reaction has combustion energy equivalent to the enthalpy of the reaction is . Thus, option B is correct.
Learn more about enthalpy of reaction, here:
brainly.com/question/1657608
Answer:
The mass of an atom is found in its nucleus.
Explanation:
An atom is made of three different particles: protons, neutrons and electrons.
Protons (positive charge) and neutrons (no charge) each have a mass of 1 AMU. They are both found in the nucleus (centre) of the atom.
Electrons (negative charge) are considered to have a mass of 0. Their mass is not actually 0, but very close so we do not count them. They are not in the nucleus, but found in shells surrounding the atom.
To calculate the mass of an atom, we add the number of protons and the number of electrons.
m = P + N
Temperature. Water is an example. When water is at room temp. its liquid. When water is at boiling temp. It is a gas. And when water is at freezing temp. Its a solid.
