Answer:
Decomposition
Explanation:
First, you have one compound, then they break up, or decompose, into two compounds.
The purpose of using distilled water in the cuvette of the spectrophotometer is to calibrate the instrument. It is generally considered that distilled water shows zero absorbance and 100 % transmittance. So, to zero out the absorbance of compounds other than the analyte being determined, distilled water is used as a blank.
If the unknown being determined is prepared using ethanol as the base solution, the blank used must be ethanol. This is because absorbance if any from the solvent, ethanol must be zeroed out as when the measurement of the actual unknown is being made, the absorbance of the solvent does not interfere.
Answer: 1. 
2. 3 moles of 
: 2 moles of 
3. 0.33 moles of : 0.92 moles of
4. is the limiting reagent and is the excess reagent.
5. Theoretical yield of 
is 29.3 g
Explanation:
To calculate the moles :
The balanced chemical equation is:
According to stoichiometry :
3 moles of require = 2 moles of
Thus 0.33 moles of will require=
of
Thus is the limiting reagent as it limits the formation of product and is the excess reagent.
As 3 moles of give = 2 moles of
Thus 0.33 moles of give = of
Theoretical yield of 
Thus 29.3 g of aluminium chloride is formed.
The answer is A, because of the chemical reaction taking place color can change (as in this case). Hope it helps!
Answer:
An Element is a substance made up of only one type of atom as like gold, copper, oxygen, etc.
Copper sulphate with molecular formula 
, the elements are copper, sulphur and oxygen. It is formed by combination of 
cation and 
anion.
Copper sulphide with molecular formula 
, the elements are copper and sulphur. It is formed by combination of cation and 
anion.
