Answer:
moles H₂O = 10
Explanation:
The mass of Na₂CO₃⋅xH₂O is 3.837 g and the mass of Na₂CO₃ is 1.42g
Therefore the mass of xH₂O is 3.837 - 1.42 = 2.417 g
The molar mass of Na₂CO₃ is 106 g/mol and for H₂O is 18 g/mol
The moles of Na₂CO₃ and H₂O in the sample are:
Na₂CO₃ = 1.42 / 106 = 0.01340 moles
H₂O = 2.417 / 18 = 0.1343
Now using rule of three :
1 mole of Na₂CO₃ has x moles of H₂O
0.01340 moles of Na₂CO₃ has 0.1343 moles of H₂O
x = 1 * 0.1343 / 0.01340 = 10
N -3
Ba +2
Sr +2
F -1
I -1
Ca +2
Mg +2
S -2
S -2
Al +3
//
Ba3N2
SrF2
CaI2
MgS
Al2S3
//
I don't really understand 2.
%(NaHCO3)= ((mass NaHCO3)/(mass NaHCO3 + mass water))*100%
m=Volume*Density
Density of water =1 g/ml
m(water) = Volume(water)*Density(water) = 600.0 ml * 1g/ml=600g water
%(NaHCO3)= ((20.0 g)/(20.0 g + 600 g))*100%=0.0323*100%=32.3%
To know the answer, you either know what is really the
nature and chemistry of a sugar solution. You can also know the answer by
knowing the meaning of entropy. Entropy is often interpreted as the degree of
disorder or randomness in the system. So the correct statement is that the
system becomes more disordered and has an increase in entropy.
