Rust formation is represented as iron + oxygen → rust + energy. which describes this reaction?
rust formation is an exothermic reaction because it absorbs energy.
rust formation is an exothermic reaction because it releases energy.
rust formation is an endothermic reaction because it absorbs energy.
rust formation is an endothermic reaction because it releases energy.

B

Explanation:

Iron + oxygen= rust+energy

Therefore, it is releasing energy.

Answer : The correct option is, Rust formation is an exothermic reaction because it releases energy.

Explanation :

Endothermic reaction : It is a type of chemical reaction in which the energy is absorbed from the surrounding.

Exothermic reaction : It is a type of chemical reaction in which the energy is released into the surrounding.

Iron rusting : It is a chemical process in which an iron nail react with water and oxygen to give iron oxide as a product. Rusting of iron is an oxidation-reduction reaction.

The rust formation is represented as:

From the this we conclude that, the energy is released during the rusting formation. That means, it is an exothermic process.

Hence, the correct option is, Rust formation is an exothermic reaction because it releases energy.

beta decay is the answer

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"