Answer:
The amount of Mg was enough
Explanation:
In this case, we have to start with the <u>reaction</u> between 
and 
, so:
If we check <u>the reaction is already balanced</u>. Now, we can do some stoichiometry to calculate the amount of Mg. The first step is the number of moles of . To this we have to calculate the molar mass of first, so:
Cu: 63.55 g/mol and O: 16 g/mol. So, (63.55+16)= 79.55 g/mol.
Now, we can calculate the moles:
The <u>molar ratio</u> between and is 1:1, so:
.
Now we can <u>calculate the mass of M</u>g if we know the atomic mass of Mg (24.305 g/mol). So:
<u>With this in mind, the student added enough Mg to recover all the Cu.</u>
Note: The HCl doesn't take a role in the reaction. The function of HCl is to dissolve the .
I hope it helps!
Answer:
Explanation:
Phenolphthalein is a protonated indicator and methyl orange is a basic indicator having hydroxyl ionisable part .
Phenolphthalein can be represented by the following formula
HPh which ionizes in water as follows
HPh + H₂O ⇄ H₃O⁺ + Ph⁻
( colourless ) ( pink )
In acidic solution it is in the form of protonated Hph form which is colourless
In basic medium , it ionises to give H₃O⁺ and unprotonated Ph⁻ whose colour is pink .
D. I hope you have a good morning
- Josie Annette
Atoms are the basic building blocks of ordinary matter. Atoms can join together to form molecules, which in turn form most of the objects around you.
Answer:
5 g
Explanation:
The heat required to vaporize ice is the sum of
i) Heat required to melt ice at 0°C
ii) Heat required to raise the temperature from 0°C to 100°C
iii) Heat required to vaporize water at 100°C
Thus;
H = nLfus + ncθ + nLvap
H= n(Lfus + cθ + Lvap)
Lfus = 6.01 kJ/mol
Lvap = 41 kJ/mol
c = 75.38
n =?
2100 = n(6.01 + 75.38(100) + 41)
n = 2100 KJ/7585.01 kJ/mol
n = 0.277 moles
Mass of water = number of moles * molar mass
Mass of water = 0.277 moles * 18 g/mol
Mass of water = 5 g
