Answer:
Mass = 6.538 g
Explanation:
Given data:
Mass of zinc hydroxide produced = 9.65 g
Mass of zinc required = ?
Solution:
Chemical equation:
Zn + 2MnO₂ + H₂O → Zn(OH)₂ + Mn₂O₃
Number of moles of zinc hydroxide:
Number of moles = mass/molar mass
Number of moles = 9.65 g/ 99.42 g/mol
Number of moles = 0.1 mol
now we will compare the moles of zinc and zinc hydroxide,
Zn(OH)₂ : Zn
1 : 1
0.1 : 0.1
Mass of zinc required:
Mass = number of moles × molar mass
Mass = 0.1 mol × 65.38 g/mol
Mass = 6.538 g
Answer:
1.40*10⁻² M
Explanation:
We have the solubility formula
Solubility,
S = KH*P
where
KH = measure of hardness of water / carbonate hardness = 3.50*10⁻² mol/L.atm
P = atmospheric pressure = 0.400 atm
Hence, we have
S = KH*P
= (3.50*10⁻² mol/L.atm)*(0.400 atm)
= 1.40*10⁻² mol/L
But 1 mol/L = 1 M,
Hence, the answer (1.40*10⁻² mol/L
) is equivalent to
= 1.40*10⁻² M
B. positive because y increases as x does. It it were negative y would decrease as x increases and it would be 0 if y stayed the same as x increases.
