The law of conservation of mass say that, in a chemical reaction, the mass of the reagents will always be equal to the mass of the products. This is shown in the reaction given below.
- Mass of the reagent: 100 g.
- Mass of the products: 56 + 44 = 100 g.
Alpha particles, also called alpha ray or alpha radiation, consist of two protons and two neutrons bound together into a particle identical to a <u>helium-4 nucleus. </u>They are generally produced in the process of alpha decay, but may also be produced in other ways.
Composition: 2 protons, 2 neutrons
Mass: 6.644657230(82)×10−27 kg; 4.0015061...
Electric charge: +2 e
Symbol: α, α2+, He2+
Answer:
-1104 kJ/mol
Explanation:
The change in the enthalpy of a reaction is equal to the difference between: the sum of the enthalpy changes of the bonds broken and the sum of the enthalpy changes of the bonds formed.
The bonds broken correspond to the cleavage of bonds of the reactants, the bonds formed correspond to the bonds of the products:
- we only break oxygen O=O bond, since carbon is not bonded to anything;
- we form two C=O bonds in carbon dioxide.
Therefore, the enthalpy change is calculated by:

Chromium phosphate pentahydrate