Petroleum is a mixture of hydrocarbons. Each hydrocarbon consists of carbon and hydrogen atoms. A hydrocarbon contains carbon chain and its boiling and melting points increase with increase in length of the carbon chain. The length of the carbon chain increases with increase in the number of carbon atoms forming bonds. Therefore, the boiling point of hydrocarbon increases with increase in the number of carbon atoms.
(Answer) (2) increase in the number of carbon atoms.
Answer:
c) CH₃Cl
Explanation:
Due the relative abundance of chlorine and bromine. It is possible to determine which of the halogens is present in a mass spectrum of a organic compound:
The Cl-35, Cl-37 have a relative abundance of 75/25; Br-79 and Br-81 of 50/50.
For that reason, if a compound has a M/M+2 ratio of 75:25 you can be sure the compound has 1 Cl in its structure. Thus, the only possible structure is:
<h3>
c) CH₃Cl</h3>
Answer:
The pH of a solution containing an amphetamine (with pKb of 4.2) concentration of 250 mg/l is 10.5
Explanation:
To solve the question we note that the
The mass of amphetamine = 250 mg/l
The molar mass of amphetamine = 135.2062 g/mol
Number of moles of amphetamine = (250 mg)/(135.2062 g/mol) = 1.85×10⁻³ moles
That is the initial concentration of amphetamine = 1.85×10⁻³ M
We have
therefore
Which gives 6.3×10⁻⁵
x = 0.0003116 = [OH⁻] = [C₉H₁₃NH⁺]
However x = [OH⁻] = 3.116×10⁻⁴
pOH = -log[OH⁻] = -log(3.116×10⁻⁴) = 3.506
pH = 14 - pOH
= 14 - 3.506
= 10.49
≈ 10.5