We know that molarity = mol/L, so:
1.5 M = x mol/0.345 L
1.5 M * 0.345 L = x mol => 0.5175 mol
0.5175 mol/0.250 L = 2.07 M
Your new molarity of the solution will be 2.07 M.
The new volume : 21.85 ml
<h3>Further explanation</h3>
Given
V1=25,0 ml
P1=725 mmHg
T1=298K is converted to
T2=273'K
P2=760 mmHg atm
Required
V2
Solution
Combined gas law :

Input the value :
V2=(P1.V1.T2)/(P2.T1)
V2=(725 x 25 ml x 273)/(760 x 298)
V2=21.85 ml
35 m/s = 210000 cm/min
35*600=210000
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