Answer:
a. Phosphoric Acid
b. Acetic Acid
c. Hypochlorous Acid
Explanation:
A buffer works when the pH of this one is in pKa ± 1. That means, to find which buffer system works in some pH you need to find pKa:
pKa = -log Ka
<em>pKa Acetic acid:</em>
-log1.8x10⁻⁵ = 4.74
<em>pKa phosphoric acid:</em>
-log7.5x10⁻³ = 2.12
<em>pKa hypochlorous acid:</em>
-log3.5x10⁻⁸ = 7.46
a. For a pH of 2.8 the best choice is phophoric acid because its effective range is: 1.12 - 3.12 and 2.8 is between these values.
b. pH 4.5. Acetic acid. effective between pH's 3.74 - 5.74
c. pH 7.5. Hypochlorous acid that works between 6.46 and 8.46
<u>Answer:</u> The time taken by the reaction is 84.5 seconds
<u>Explanation:</u>
The equation used to calculate half life for first order kinetics:

where,
= half-life of the reaction = 9.0 s
k = rate constant = ?
Putting values in above equation, we get:

Rate law expression for first order kinetics is given by the equation:
......(1)
where,
k = rate constant = 
t = time taken for decay process = 50.7 sec
= initial amount of the reactant = ?
[A] = amount left after decay process = 0.0741 M
Putting values in equation 1, we get:
![0.077=\frac{2.303}{50.7}\log\frac{[A_o]}{0.0741}](https://tex.z-dn.net/?f=0.077%3D%5Cfrac%7B2.303%7D%7B50.7%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B0.0741%7D)
![[A_o]=3.67M](https://tex.z-dn.net/?f=%5BA_o%5D%3D3.67M)
Now, calculating the time taken by using equation 1:
![[A]=0.0055M](https://tex.z-dn.net/?f=%5BA%5D%3D0.0055M)

![[A_o]=3.67M](https://tex.z-dn.net/?f=%5BA_o%5D%3D3.67M)
Putting values in equation 1, we get:

Hence, the time taken by the reaction is 84.5 seconds
The energy required to raise the temperature of 3 kg of iron from 20° C to 25°C is 6,750 J( Option B)
<u>Explanation:</u>
Given:
Specific Heat capacity of Iron= 0.450 J/ g °C
To Find:
Required Energy to raise the Temperature
Formula:
Amount of energy required is given by the formula,
Q = mC (ΔT)
Solution:
M = mass of the iron in g
So 3 kg = 3000 g
C = specific heat of iron = 0.450 J/ g °C [ from the given table]
ΔT = change in temperature = 25° C - 20°C = 5°C
Plugin the values, we will get,
Q = 3000 g × 0.450 J/ g °C × 5°C
= 6,750 J
So the energy required is 6,750 J.
Answer:
yes it is true they apply necessary safety measures
Answer:
5-chloro-2-methylcyclohexanol
Explanation:
There is no structure for the compound, but we can analyze the proposed options using the IUPAC rules to name organic compounds.
IUPAC rules state that to name an organic compound, first we have to identify the priorities for the functional groups present in the compound. <em><u>In this case, the priority functional group is the alcohol group</u></em>, <u><em>so we will start the counting of the carbons in this group.</em></u> Then, the counting of carbon atoms is followed by the next substituents so they have the lowest possible numbers, <em><u>in this case, we can assign the number 2 to the methyl group and 5 to the chloride group</u></em>, and name the compound in alphabetical order, using commas to separate the words from the numbers and with no space between the words.
Since the other options involve: <u>high countings for the susbtituents groups (</u><u>3</u><u>-chloro-</u><u>6</u><u>-methylcyclohexanol)</u>, <u>wrong assignation of priority functional group (</u><u>1-chloro</u><u>-4-methylcyclohexanol), wrong sequence of counting in the compound (</u><u>2-methyl-3-chloro</u><u>cyclohexanol) and no alphabetical order to name the compound (2-</u><u>methyl</u><u>-5-</u><u>chloro</u><u>cyclohexanol), </u><u>the correct option is:</u>
5-chloro-2-methylcyclohexanol
Have a nice day!