Answer:
the weakest acid is B) HIO
Explanation:
pKa = - log Ka
the higher the value of pKa, the lower the dissociation, therefore, an acid will be stronger the lower its pKa.
a) HC2H3O2; Ka = 1.8 E-5
⇒ pKa1 = - Log (1.8 E-5) = 4.745
b) HIO; Ka = 23 E-11
⇒ pKa2 = - Log ( 23 E-11 ) = 9.638
c) HBrO; Ka = 23 E-9
⇒ pKa3 = - Log ( 23 E-9 ) = 7.638
d) HClO; Ka = 2.9 E-8
⇒ pKa4 = - Log ( 2.9 E-8 ) = 7.537
e) HCO2H; Ka = 63 E-5
⇒ pKa5 = - Log ( 63 E-5 ) = 3.200
from the values pKa, we places the acids from the weakest to the least weak:
1) pKa2; HIO (weakest)
2) pKa3
3) pKa4
4) pKa1
5) pKa5
Answer:
12.02 g
Explanation:
From the question given above, the following data were obtained:
Half life (t½) = 2 days
Original amount (N₀) = 96 g
Time (t) = 6 days
Amount remaining (N) =..?
Next, we shall determine the rate of disintegration of the isotope. This can be obtained as follow:
Half life (t½) = 2 days
Decay constant (K) =?
K = 0.693 / t½
K = 0.693 / 2
K = 0.3465 /day
Therefore, the rate of disintegration of the isotope is 0.3465 /day.
Finally, we shall determine the amount of the isotope remaining after 6 days as follow:
Original amount (N₀) = 96 g
Time (t) = 6 days
Decay constant (K) = 0.3465 /day.
Amount remaining (N) =.?
Log (N₀/N) = kt / 2.303
Log (96/N) = (0.3465 × 6) / 2.303
Log (96/N) = 2.079/2.303
Log (96/N) = 0.9027
Take the anti log of 0.9027
96/N = anti log (0.9027)
96/N = 7.99
Cross multiply
96 = N × 7.99
Divide both side by 7.99
N = 96 /7.99
N = 12.02 g
Therefore, the amount of the isotope remaining after 6 days is 12.02 g
Answer:
More than three decade the temperature of earth is increasing equally by the rate of 0.8 Celsius (1.4 Fahrenheit). It is going to be very harmful for the human being as well animals. The global warming is the main reason and hole in the ozone layer had been the cause of increasing the temperature of the earth. Humans are also involved in cause in temperature of earth by cutting forests and making land suitable for residence and not planting more trees instead of the cut trees.
A mixture is a portion of matter made up of two or more substances called constituents. Mixtures are the product of the mechanical joining of substances without change in chemical nature, and therefore, each constituent retains its properties.
the option 4
A. good conductors - copper, aluminium
b. fair conductors - carbon,human body
c. insulator - paper, wood
