Answer:
A chemical change is a change in the chemical makeup of a substance and results in a new substance. Ice and water both have the same chemical makeup - ice is just a different state and has the same atoms but in an expanded form.
Explanation:
Empirical formula is calculated as follows
calculate the moles of each element, that is % composition/ molar mass
molar masses ( Si= 28.09g/mol , Cl= 35.5 g/mol, I=126.9 g/mol)
moles of silicon = 7.962/28.09g/mol= 0.283 moles
moles of chlorine = 20.10 / 35.5g/mol = 0.566 moles
moles of iodine= 71.94 / 126.9 g/mol= 0.567 moles
divide each mole with smallest mole (0.283)
that is silicon = 0.283/0.283= 1 mole
chlorine = 0.566/0.283= 2 mole
Iodine= o.567/0.283= 2 moles
empirical formula is therefore= SiCl2I2
Answer:Cell reaction is going forward.
Explanation:
For any chemical reaction to be spontaneous or to move in forward direction the ΔG ,the Gibbs free energy must be negative.
The cell potential of a battery is positive for a spontaneous reaction, so for a battery to give output its cell potential must be positive.
Thermodynamics and electro-chemistry are related in the following manner:
ΔG=-nFE
n=number of electrons involved
F=Faradays constant
E=cell pottential of battery
so from the above equation ΔG would only be negative when E cell that is the cell potential is positive.
For a battery which is being used its cell potential is positive and hence the ΔG would be negative. So the cell reaction occurring would be in forward direction as ΔG is negative.
when the cell potential Ecell is 0 then ΔG is also zero then the reaction occurring in battery would be at equilibrium.
When the cell potential Ecell is - then ΔG is positive and the reaction would be occurring backwards.
