When sugar is heated it melts and then caramelize giving of water. After this, it turns blank (carbon) and then coverts to co2 (carbon dioxide) .
So, heating of sugar is an endothermic , decomposition and oxidation reaction.
When Ammonium Chloride is heated , it directly goes from solid state to vapour state without changing into liquid state.
So, heating of Ammonium Chloride is an example of sublimation reaction.
<span>The number of atoms in 4.75 moles of gold (Au) is found using Avogadro's number, which is 6.022Ă—1023 mol-1. Determine the number of atoms by multiplying 4.75 moles by Avogadro's number. The number of atoms in 4.75 moles of gold is 2.8605172125000205e24.</span>
Answer:
a
Explanation:
Its renewable because of the reproduction and the are born every spring
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.
