Answer : The mass of aluminium (Al) is 0.413 g
Solution : Given,
Volume of 
at STP = 513 ml = 0.513 L ( 1 L = 1000 ml )
Molar mass of aluminium = 26.98 g/mole
First we have to calculate the moles of .
At STP,
1 mole occupies 22.4 L volume
now, 0.513 L gives 
moles of
The moles of = 0.0229 moles
The Net balanced chemical reaction is,
From the balanced chemical reaction, we conclude that
2 moles of Aluminium (Al) produces 3 moles of hydrogen gas
Now the number of moles of aluminium required in 0.0229 moles of hydrogen gas = 
= 0.0153 moles
Now we have to calculate the mass of aluminium.
Mass of aluminium = number of moles × Molar mass = 0.0153 moles × 26.98 g/mole = 0.413 g
The mass of aluminium required is 0.413 g.
Answer:
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Answer:
0.77 M
Explanation:
Molarity is the concentration of a solution per liter
C= concentration
n= number of moles
V= volume of solution
The formula we will use is C= n/V
C= n/V
C= (1.93 mol NaCl)/(2.5 L of solution)
C= 0.772 mol/L
Since this concentration is given in moles per liters of a solution, this concentration is also the molarity.
C= 0.772 mol/L
*Include two significant digits in final answer*
M= 0.77 M
Seen in the electrons, which are found in the atomic cloud surrounding the nucleus.
First, we should get moles acetic acid = molarity * volume
=0.3 M * 0.5 L
= 0.15 mol
then, we should get moles acetate = molarity * volume
= 0.2 M * 0.5L
= 0.1 mol
then, we have to get moles of OH- which added:
moles OH- = molarity * volume
= 1 M * 0.02L
= 0.02 mol
when the reaction equation is:
CH3COOH + OH- → CH3COO- + H2O
moles acetic acid after adding OH- = (0.15-0.02)
= 0.13M
moles acetate after adding OH- = (0.1 + 0.02)
= 0.12 M
Total volume = 0.5 L + 0.02 L= 0.52 L
∴[acetic acid] = moles acetic acid after adding OH- / total volume
= 0.13mol / 0.52L
= 0.25 M
and [acetate ) = 0.12 mol / 0.52L
= 0.23 M
by using H-H equation we can get PH:
PH = Pka + ㏒[salt/acid]
when we have Ka = 1.8 x 10^-5
∴Pka = -㏒Ka
= -㏒ 1.8 x 10^-5
= 4.7
So by substitution:
∴ PH = 4.7 + ㏒[acetate/acetic acid]
= 4.7 + ㏒(0.23/0.25)
= 4.66
