3s.f as that's what the numbers in the question are given to
So the answer is 0.978
The process which has taken place is called CRYSTALLIZATION.
Generally, crystallization is the process by which solid crystals are precipitated from solution. Crystallization can also occur when a crystal melt or when a crystal get deposited directly from a gas, although these cases are rarer compare to crystals forming from solutions.
When a substance changes into a different substance, you are observing its chemical properties.
In a physical change, the substance must <em>not </em>change into a different substance.
The physical and chemical properties of a substance do <em>not</em> change.
Answer:
0.940mol &
0.000301mol respectively.
Explanation:
number of moles = given mass / molar mass
given mass of Nacl = 55g Molar mass = 23 + 35.5
n=m/M = 55g/58.5g/mol = 0.940mol
note- (add the atomic weights of sodium and chlorine to get the molar mass of Nacl.) = 58.5g/mol
similarly, NaCO3 = 23 + 12 + 16*3 = 83g/mol
n=m/M = 0.025g/83g/mol = 3.01 * 10^-4 = 0.000301mol
extra: If you ever get asked to put it in number of particles just use the relation of 1mole = 6.02 * 10^23 particles.
