<span>Balanced half-reaction: Au</span>⁺<span>(aq) </span>→ <span> Au</span>³⁺(aq) + 2e⁻.
Oxidation reaction is increasing of oxidation number of element, because element or ion lost electrons in chemical reaction.
Gold lost two electrons and change oxidation number from +1 to +3.
Reduction is lowering oxidation number because element gain electrons.
This law states that, despite chemical reactions or physical transformations, mass is conserved — that is, it cannot be created or destroyed — within an isolated system. In other words, in a chemical reaction, the mass of the products will always be equal to the mass of the reactants.
I looked this up but hope it helps!
Answer:
mass and volume are independent. Two objects with the same volume can have different masses hence they can have different densities
Explanation:
The mass of atoms their size and how they are arranged determine the density
Answer:
Mixing of salt is physical change.
Explanation:
Mixing of salt is physical change because no chemical reaction occur between them. Sand is non polar while salt is polar.
Physical Change:
The changes that occur only due to change in shape or form but their chemical or internal composition remain unchanged.
These changes were reversible.
They have same chemical property.
These changes can be observed with naked eye.
Chemical change:
The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.
These changes are irreversible
These changes occur due to chemical reactions
These may not be observed with naked eye