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Use the IUPAC rules to name the following structures:
A. CH3
I
CH3CH2CH2CH2CHCH3
I
CH2
I
CH3
B. CH3
I
CH2CH2CH2CH2CH2CH2CH3
Draw the structure of each of the following alkanes.
A. 2,3,4 - trimethylpentane
B. 2 - methylheptane
Calculate the standard entropy values for the following reactions at 25°C.
1. N2(g) + 3H2(g) ⟶ 2NH3(g)
2. H2(g) + Cl2(g) ⟶ 2HCl(g)
3. 2CO2(g) + O2(g) ⟶ 2CO2(g)
4. 3O2(g) ⟶ 2O3(g)
5. 2NH3 (g) + CO2 (g) ⟶ NH2CONH2 (aq) H2O(l)
The orbital period of Planet A is 16 years and its average distance to Star B is
5.25 a.u. Another planet called Planet C has an average distance of 10.3 a.u.
from Star B, using Kepler’s Third Law of Planetary Motion, compute the orbital
period of Planet C to Star B in days.
Write the six steps in hypothesis testing in each of the following studies. Take note, the p-value is already given.
The average family size in the Philippines was reported as 4.25. A random sample of families in a particular street resulted in the following family sizes:
5, 6, 7, 4, 3, 8, 2 and 9
\At 0.10, is the average family size more than the national average?
(p-value = 0.0961)
Make a Number system convert to convert a number of any number system to another number system. Implement only Binary, Base 5, Octal, Decimal, and Hexa number systems. Converter should be developed in Python language.
Two equal resistors of 15 kΩ each are connected in series across a 120 V source. A voltmeter when connected across each read 48 V in each case. Determine the resistance of the voltmeter.
Question 23
25.00 cm3 of a 0.7892 mol.dm-3 solution of potassium hydroxide is transferred to an empty 350.00 cm3 volumetric flask. This flask is made up to the mark with distilled water and then shaken well. The concentration of the potassium hydroxide in this second flask is:
a. 0.01109 mol.dm-3
b. 0.05637 mol.dm-3
c. 0.7892 mol.dm-3
d. 17.74 mol.dm-3
e. None of the above.
Question 24
What is the molarity of glacial acetic acid (CH3COOH, Mr = 60.05 g/mol) at 25°C given that the density of acetic acid at that temperature is 1.049 g/mL?
a. 0.0174 M
b. 0.057 M
c. 57.2 M
d. 60.1 M
e. None of the above
Question 25
Calculate the molarity of a KF (aq) solution containing 116.2 g of KF in 3.00 L of solution?
a. 0.02585 M
b. 0.667 M
c. 38.7 M
d. 58.1 M
e. None of the above
Question 19
Suppose that a solution is prepared by mixing 25 mL (0.22 mol, 16 g) of pentane (the solute) with 45 mL (0.34 mol, 30 g) of hexane (the solvent). If the volumes add on mixing, answer questions 19-21 below.
Calculate the molality of the pentane
a. 3.1 mol/kg
b. 4.8 mol/kg
c. 7.3 mol/kg
d. 3.1 mol/L
e. 7.3 mol/L
Question 20
Calculate the molarity of the pentane?
a. 3.1 mol/kg
b. 7.3 mol/kg
c. 3.1 mol/L
d. 7.3 mol/L
e. 45.8 mol/L
Question 21
What is the mole fraction of the pentane?
a. 0.35
b. 0.39
c. 0.64
d. 39%
e. 64 %
Question 22
If I prepare a solution by adding 25 mL of 2.0 M NaOH into a 500 mL volumetric flask, and filling the flask to the mark with water, what will the final concentration of the solution be?
a. 0.05 M
b. 0.10 M
c. 0.5 M
d. 2.0 M
e. 40.0 M
Question 14
In the above reaction in question 13, 2 moles of Mg and 5 moles of O2 are allowed to react.
Which reagent is the limiting reagent?
a. Mg
b. O2
c. MgO
d. There is no limiting reagent
e. Both Mg and O2 are limiting reagents
Question 15
What is the maximum number of moles of MgO that can be formed?
a. 1 mol
b. 2 mol
c. 5 mol
d. 40.3 mol
e. 80.6 mol
Question 16
Calculate how many moles of the excess reagent remain unreacted.
a. 1 mol
b. 2 mol
c. 4 mol
d. 5 mol
e. No excess reagent remains unreacted
Question 17
Suppose that the actual moles of MgO produced was 0.5 mol, what is the percentage yield of MgO?
a. 0.62%
b. 1.2%
c. 10%
d. 25%
e. 50%
Question 18
The value of a solution concentration unit that may change with temperature is
a. molarity.
b. mole fraction.
c. molality.
d. mole percentage.
e. weight percentage.
#340153 on Dec 2023