Analytic chemistry
I think
Answer:
54.75 mL
Explanation:
First calculate the number of moles of NaCl in the 150mL solution of NaCl
0.0365 moles should be present on 1000cm3 or 1dm3 of water.
1L = 1 dm3
1 mL = 1 / 1000 dm3
150 mL = 150/1000 dm3 = 0.15 dm3
If x moles are present in 0.15 dm3,
x/ 0.15 = 0.0365
We get x= 0.0365 × 0.15 mol
Now x amount of moles should be taken from the initial 0.100 M NaCl solution
So 0.1 moldm-3 = 0.0365× 0.15 mol / V
we get V = 0.05475 dm3
V= 0.05475 L
V= 54.75 mL
The answer to the question is B D E
Displacement reaction
Because Al goes to SO4 and
Cu goes from SO4 to Cu
This happens because Al is more reactive (higher up in the reactivity series) than Cu
Answer:
n=6 to n=3 (B)
Explanation:
Energy of an electron present in the
orbit is directly proportional to
.Hence a transistion from one orbit to another orbit emits an energy proportional to the difference of their squares of the orbits. that is if an electron travels from orbit n1 to orbit n2 then it emits an energy corresponding to
.So in the above question the highest energy emission occurs when an electron moves from n=6 to n=3.(Highest difference of energy levels).