Answer:
The new volume of the balloon be
.
Explanation:
We have,
Initial volume is 556 cm ³
The temperature of the balloon decreases from 278 K to 231 K.
We need to find the new volume of the balloon if the pressure is constant.
The Charles law states that at constant pressure, the volume of gas is directly proportional to its temperature i.e.
, P is constant


So, the new volume of the balloon be
.
Fluorescence
when a substance absorbs external radiation in any form and gives of a glow or luminescence it is considered as Fluorescence.
Answer:
The question is incomplete.

Answer:
<u> </u><u>85.952 ml</u>
needed to titrate the excess complexing reagent .
Explanation:
Lets calculate
After addition of 80 ml of EDTA the solution becomes = 20 + 70 = 90 ml
As the number of moles of
=
=
=0.01172
Molarity = 
=
=0.000586 moles
Excess of EDTA = concentration of EDTA - concentration of CoSO4
= 0.009005 - 0.000586
= 0.008419 M
As M1V1 ( Excess of EDTA ) = M2V2 


V2 =85.952 ml
Therefore , <u>85.952 ml </u>
needed to titrate the excess complexing reagent .
The reaction would be as shown below;
Na2SO4 + Ca(NO3)2 = CaSO4 + 2 NaNO3
The moles of NaSO4 will be;
= 0.05 × 0.0154 = 0.00077 moles
While the number of moles of Ca(NO3)2
= 0.05 × 0.0128 = 0.00064 moles
The mole ratio of sodium sulfate and calcium nitrate is 1:1
Ca(NO3)2 is the limiting reactant, so ignoring the Ksp of CaSO4, zero percent of the Ca^2+ ions remain unprecipitated.