Amphetamine (c9h13n is a weak base with a pkb of 4.2. calculate the ph of a solution containing an amphetamine concentration of 205 mg/l.

The answer to the question is;

The pH of a solution containing an amphetamine (with  pKb of 4.2) concentration of 205 mg/l is  10.4.

Explanation:

To solve the question we note that the

The mass of amphetamine = 205 mg/l

The molar mass of amphetamine  = 135.2062 g/mol

Number of moles of amphetamine  = (205 mg)/(135.2062 g/mol) = 1.5×10⁻³ moles    

That is the initial concentration of amphetamine = 1.5×10⁻³ M

We have therefore = = 6.3×10⁻⁵

Then   = 6.3×10⁻⁵

Which gives 6.3×10⁻⁵ =  

Solving, we get  

From which by factorizing gives (x+3.42×10⁻⁴)×(x-2.79×10⁻⁴) = 0

That is x = -3.42×10⁻⁴ or 2.79×10⁻⁴ which gives x= 2.79×10⁻⁴  since we are dealing with concentration

However x = [OH⁻] = 2.79×10⁻⁴

pOH = -log[OH⁻] = -log(2.79×10⁻⁴) =   3.5538

pH = 14 - pOH = 14 - 3.5538 = 10.446 ≈ 10.4

the pH of a solution containing an amphetamine concentration of 205 mg/l = 10.4.

c. 7/3

step-by-step explanation:

a rational number is like pi- it is a repeating decimal.

a. is -1.8

b. 2.236068

c. 2.3333333333333333333

d.   is 3

i hope that ! =)

the aurora is formed when charged particles emitted from the sun during a solar flare penetrate the earth's magnetic shield and collide with atoms and molecules in our atmosphere. these collisions result in countless little bursts of light, called photons, which make up the aurora.

auroras are generated by charged solar particles hitting molecules in earth's atmosphere. this usually happens in high latitudes, because our planet’s magnetic field tends to funnel these particles toward the poles. that’s why it can be experienced in northern ohio.