Explanation :
The balanced chemical reaction is,

The expression for the rates of consumption of the reactants are:
The rate of consumption of
= ![-\frac{1}{5}\frac{d[Br^-]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7B1%7D%7B5%7D%5Cfrac%7Bd%5BBr%5E-%5D%7D%7Bdt%7D)
The rate of consumption of
= ![-\frac{d[BrO_3^-]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7Bd%5BBrO_3%5E-%5D%7D%7Bdt%7D)
The rate of consumption of
= ![\frac{1}{6}\frac{d[H^+]}{dt}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B6%7D%5Cfrac%7Bd%5BH%5E%2B%5D%7D%7Bdt%7D)
The expression for the rates of formation of the products are:
The rate of consumption of
= ![+\frac{1}{3}\frac{d[Br_2]}{dt}](https://tex.z-dn.net/?f=%2B%5Cfrac%7B1%7D%7B3%7D%5Cfrac%7Bd%5BBr_2%5D%7D%7Bdt%7D)
The rate of consumption of
= ![+\frac{1}{3}\frac{d[H_2O]}{dt}](https://tex.z-dn.net/?f=%2B%5Cfrac%7B1%7D%7B3%7D%5Cfrac%7Bd%5BH_2O%5D%7D%7Bdt%7D)
Answer:
1. 
2. 
Explanation:
Hello,
1. In this case, since the volume of the rock is obtained via the difference between the volume of the cylinder with the water and the rock and the volume of the cylinder with the water only:

Thus, the density turns out:

2. In this case, given the density and mass of aluminum we can compute its volume as follows:

Moreover, as the volume is also defined in terms of width, height and length:

The height is computed to be:

Best regards.
Number 4 is
-Oxidation occurs at the anode, while reduction occurs at the cathode. Recharging a battery involves the conversion of electrical energy to chemical energy. During recharging, there is movement of electrons from an external power source to the anode, and on the other side electrons are removed from the cathode.