Answer:
1.58x10⁻⁵
2.51x10⁻⁸
0.0126
63.10
Explanation:
Phenolphthalein acts like a weak acid, so in aqueous solution, it has an acid form HIn, and the conjugate base In-, and the pH of it can be calculated by the Handerson-Halsebach equation:
pH = pKa + log[In-]/[HIn]
pKa = -logKa, and Ka is the equilibrium constant of the dissociation of the acid. [X] is the concentrantion of X. Thus,
i) pH = 4.9
4.9 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = - 4.8
[In-]/[HIn] = 
[In-]/[HIn] = 1.58x10⁻⁵
ii) pH = 2.1
2.1 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -7.6
[In-]/[HIn] = 
[In-]/[HIn] = 2.51x10⁻⁸
iii) pH = 7.8
7.8 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -1.9
[In-]/[HIn] = 
[In-]/[HIn] = 0.0126
iv) pH = 11.5
11.5 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = 1.8
[In-]/[HIn] = 
[In-]/[HIn] = 63.10
Answer:
Explanation:
Given parameters:
Volume of CO₂ = 24cm³
time taken for the reaction to complete = 8minutes.
Unknown:
rate of reaction
Soution
The reaction rate is a measure of speed of a chemical reaction. It is often calculated using the expression below:
Reaction rate = 
Reaction rate = 
= 3cm³/min
In this reaction, 3cm³ of carbon dioxide were produced per minute
Answer:
2–methylpropene.
Explanation:
To successfully name the compound given in the question, we must observe the following:
1. Determine the functional group of the compound.
2. Locate the longest continuous carbon chain. This gives the parent name of the compound.
3. Identify the substituent group attached and locate it's position by giving it the lowest possible count.
4. Combine the above to obtain the name of the compound.
Now, let us determine the name of the compound. This is illustrated below:
1. The functional group of the compound is the double bond i.e the compound is an alkene.
2. The longest continuous carbon chain is 3 i.e propene since it is an alkene.
3. The substituent group attached is methyl i.e CH3. In this case, we'll start counting from the side of the double bond being the functional group. Therefore, the methyl group i.e CH3 is at carbon 2.
4. Therefore, the name of the compound is:
2–methylpropene
Hey there!:
The reaction is as follows:
N2(g)+ 3 H2(g) ⇌ 2 NH3(g)
At equilibrium, the concentrations of the different species are as follows.:
[NH3] = 0.105 M
[N2] = 1.1 M
[H2] = 1.50 M
The equilibrium constant for the reaction is given as follows:
Keq = [NH3]² / [N2] [H2]³
Keq = (0.105)² / [1.1] [1.50]³
Keq = 0.00296 or 0.0030
The equilibrium constant for the reaction at this temperature is 0.0030.
Hope that helps!
