Answer:
Final pressure of the gas remaining in the first container is 3.5 atm
Explanation:
Since it is given that temperature is constant , we can apply -
PV=constant , where
P = Pressure of the gas
V = Volume of the container in which the gas is contained
Initially,
For container 1 -
= 4 atm
= 6 L
Finally,
For container 2 -
= 3 atm
= 1 L
For container 1 -
= ?
= 6 L
∴ 
= 
+ 

∴ 4×6 = (
×6) +(3×1)
∴
= 3.5 atm
Solution of 0.25 M is prepared in two steps,
1) Calculate Amount of Solute:
Molar Mass of Solute: 342.3 g/mol
As we know,
Molarity = Moles / 1 dm³
or,
Moles = Molarity × 1 dm³
Putting Values,
Moles = 0.25 mol.dm⁻³ × 1 dm³
Moles = 0.25 moles
Now, find out mass of sucrose,
As,
Moles = Mass / M.mass
or,
Mass = Moles × M.mass
Putting Values,
Mass = 0.25 mol × 342.3 g.mol⁻¹
Mass = 85.57 g
2) Prepare Solution:
Take Volumetric flask and add 85.57 g of sucrose in it. Then add distilled water up to the mark of 1 dm³. Shake well! The solution prepared is 0.25 M in 1 Liter.
Chromium is in Group 6, so elemental chromium has 6 valence electrons. Therefore, chromium 3+ has three 3d-
I Believe this is the right answer:
Get a periodic table of elements. ...
Find your element on the periodic table. ...
Locate the element's atomic number. ...
Determine the number of electrons. ...
Look for the atomic mass of the element. ...
Subtract the atomic number from the atomic mass.
Hoped this helped!