John Dalton
Although the concept of the atom dates back to the ideas of Democritus, the English meteorologist and chemist John Dalton formulated the first modern description of it as the fundamental building block of chemical structures.
Answer: 4.21×10⁻⁸
Explanation:
1) Assume a general equation for the ionization of the weak acid:
Let HA be the weak acid, then the ionization equation is:
HA ⇄ H⁺ + A⁻
2) Then, the expression for the ionization constant is:
Ka = [H⁺][A⁻] / [HA]
There, [H⁺] = [A⁻], and [HA] = 0.150 M (data given)
3) So, you need to determine [H⁺] which you do from the pH.
By definition, pH = - log [H⁺]
And from the data given pH = 4.1
⇒ 4.10 = - log [H⁺] ⇒ [H⁺] = antilog (- 4.10) = 7.94×10⁻⁵
4) Now you have all the values to calculate the expression for Ka:
ka = 7.94×10⁻⁵ × 7.94×10⁻⁵ / 0.150 = 4.21×10⁻⁸
Answer:
The answer is below
Explanation:
one gallon of gasoline produces 9.50 kg of carbon.
The total number of cars = 40 million
Distance covered by each car = 7930 miles
Consumption rate of the cars per miles traveled is 23.6 miles per gallon.
Hence the annual gasoline consumption by all the cars in the United States of America = (total number of cars × Distance covered by each car) ÷ Consumption rate of the cars per miles
annual gasoline consumption by all the cars = (40000000 × 7930 miles) ÷ 23.6 miles/gallon = `1.344067797 × 10¹⁰ gallons
1.344067797 × 10¹⁰ gallons = 