They are kind of opposite processes. Chemical synthesis is execution of chemical reactions to make products. Like you take two substances, you put them together, they react and you have new a substance. For example.

here Sodium and Chlorine react to make a new substance which is Sodium Chloride.
Chemical decomposition is process of seperating a substance to different substances. There is a substance by a reaction this substance becomes two substances, Like : XY -> X+Y For example :
Answer:
1.878g
Explanation:
Volume = 30.0ml
Density = 0.626gcm−3
Mass = ?
Be careful in this kind of questions to check for the units. In this case one has to remember 1 mL equal 1 cm³ so density = 0.626g/ml
The relationship between all three parameters is given by the equationn below;
Mass = Density * Volume
Mass = 0.626g/ml * 30 = 1.878g
D. I, II, and IV. Basically everything but the temperature.
Answer:
A Fridiel craft catalyst will convert benzene to acetophenone.
Permanganate catalyst can be used to convert toluene to acetophenone.
Explanation:
Benzene can be reduced to acetophenone by the addition of anhydrous aluminium chloride, AlCl₃
The mechanism is as follows:
Benzene + Acetyl choloride → acetophenone
To convert toluene to acetophenone, the following steps are necessary:
- Oxidation of Toluene to Benzoic acid.
This is done by refluxing toluene with alkaline potassium permanganate (KMnO₄+ Na₂CO₃).
-
Benzoic acid is converted to Benzoyl chloride by treating with thioyl chloride and heating at about 80 ⁰C.
-
Benzoyl chloride is treated with methyl lithium to form Acetophenone.
Answer : 0.8663 Kg of chalcopyrite must be mined to obtained 300 g of pure Cu.
Solution : Given,
Mass of Cu = 300 g
Molar mass of Cu = 63.546 g/mole
Molar mass of
= 183.511 g/mole
- First we have to calculate the moles of Cu.

The moles of Cu = 4.7209 moles
From the given chemical formula,
we conclude that the each mole of compound contain one mole of Cu.
So, The moles of Cu = Moles of
= 4.4209 moles
- Now we have to calculate the mass of
.
Mass of
= Moles of
× Molar mass of
= 4.4209 moles × 183.511 g/mole = 866.337 g
Mass of
= 866.337 g = 0.8663 Kg (1 Kg = 1000 g)
Therefore, 0.8663 Kg of chalcopyrite must be mined to obtained 300 g of pure Cu.