For question 1:
A. Carbon, hydrogen, oxygen
Calcium, carbon, oxygen
Carbon, hydrogen
Carbon, hydrogen, oxygen
Silicon, oxygen
B. Carbon: 12, hydrogen: 22, oxygen: 11
Calcium: 1, Carbon: 1, oxygen: 3
Carbon:1, Hydrogen: 4
Carbon: 3, hydrogen: 8, Oxygen: 1
Silicon: 1 oxygen: 2
C. Table sugar: 45
Marble: 5
Natural gas: 5
Rubbing alcohol: 12
Glass: 3
For question 2: N2O
Answer:
The answer to your question is below
Explanation:
Data
Volume = 1000 ml
Concentration = 2M
molecule = NaCl
Process
1.- Calculate the number of moles of NaCl
Molarity = moles/Volume
-Solve for volume
moles = Molarity x Volume (liters)
-Substitution
moles = 2 x 1
-Result
moles = 2
2.- Determine the molar mass of NaCl
NaCl = 23 + 35.5 = 58.5 g
3.- Calculate the mass of NaCl to prepare the solution
58.5 g ----------------- 1mol
x ----------------- 2 moles
x = (2 x 58.5) / 1
x = 117g
4.- Weight 117 g of NaCl, place them in a volumetric flask (1 l), and add enough water to prepare the solution.
The most abundant isotope is the isotope with the mass number the closest to the average atomic mass.
The partial pressure of argon is:
1.63-0.71= 0.92 atm
This question is quite vague, as the initial concentration of ethanol is not provided. However, from experience I can tell you that most laboratory work is done with 98% ethanol, and not absolute ethanol (100%). So in order to calculate the final concentration, we need to take the given values, which includes the initial concentration (98%), the initial volume (50.0mL) and the final volume (100.0mL). We apply the following equation to calculate the final concentration:
C1V1 = C2V2
C1 = Initial concentration
C2 = Final concentration
V1 = Initial volume
V2 = Final volume
(98%)(50.0mL) = (C2)(100.0mL)
Therefore, the final concentration (C2) = 49%
