Hey there!
Chemical changes are changes in object's chemical compounds and chemical compositions, and often can't be reversed.
Here's an example:
If you have a piece of paper and you happen to burn it, that can't be reversed.
In other words, it can't be "un-burned". Nothing can restore it to its previous state.
Hopefully this helped!
The compound CBr4 has the highest melting point of 91°C
Answer;
K+ and NO3- ions
Explanation;
The main ions remaining are K+ and NO3- ions after pbi2 precipitation is complete.
However; There will always be tiny amounts of Pb2+ and I- ions, but most of them are in the solid precipitate.
V) the amount of sugar in the solution
C) whether the sugar is stirred
V) the temperature of the solution
C) the type of solute added
C) the type of solvent used
NP.
Answer:
Option B. 0.285m NaCl
Explanation:
To find the molality, first let find the number of mole of NaCl in the solution. This is illustrated below
Molar Mass of NaCl = 58.5 g/mol
Mass of NaCl = 10g
Number of mole of NaCl = Mass of NaCl / molar Mass of NaCl
Number of mole of NaCl = 10/58.5 = 0.1709mol
Mass of water = 600g = 600/1000 = 0.6kg
Molality = mole of solute / mass of solvent
Molality = 0.1709mol/0.6kg
Molality = 0.285mol/Kg
