Answer:
1.57×10²³ molecules
Explanation:
Given data:
Number of molecules of ethanol = ?
Volume of ethanol = 15.0 mL
Density of ethanol = 0.789 g/mL
Solution:
Mass of ethanol :
Density = mass/ volume
0.789 g/mL = mass/ 15.0 mL
Mass = 0.789 g/mL× 15.0 mL
Mass = 11.84 g
Number of moles of ethanol:
Number of moles = mass/molar mass
Number of moles = 11.84 g / 46.07 g/mol
Number of moles = 0.26 mol
1 mole contain 6.022×10²³ molecules
0.26 mol × 6.022×10²³ molecules / 1mol
1.57×10²³ molecules
<u>We are given:</u>
Volume of gas = 3.8 L
Pressure = 460 mmHg
Temperature = 77°c = (77+273)K = 350K
<u>Converting the pressure to atm:</u>
Pressure(in atm) = Pressure(in mmHg) / 760
Pressure = 460/760 = 0.6 atm
<u>Finding the number of moles:</u>
using the ideal gas equation:
PV = nRT [where R is the universal gas constant]
<em>replacing the given values in this equation</em>
(0.6)(3.8) = n(0.082)(350)
n = (0.6*3.8)/(0.082*350)
n = 0.08 moles
Answer:
Substances with high boiling points condense at the bottom and substances with lower boiling points condense on the way to the top. The crude oil is evaporated and its vapours condense at different temperatures in the fractionating column.
Explanation:
answer above
In the parallel circuit, each lamp will receive 100 volts.
<h3>
Equivalent resistance of the parallel circuit</h3>
The equivalent resistance of the parallel circuit is the inverse sum of the resistance of the two resistors in the circuit. This is as a result of different current flowing in each resistor parallel circuit arrangement.
The equivalent resistance is calculated as follows;
1/R = 1/10 + 1/10
1/R = 2/10
R = 10/2
R = 5 ohms
<h3>Current in each resistor</h3>
I = V/R
I = 100/10 = 10 A
<h3>Voltage in each resistor</h3>
V = IR
V = 10 X 10 = 100 V
Generally, for a circuit in parallel connection, same voltage will flow in each resistor of the circuit while different current will flow in the resistors.
Thus, the correct statement is, "Each lamp will receive 100 volts".
Learn more about circuit in parallel arrangement here: brainly.com/question/19929102
Molecules are pure substances. This is because a molecule has a set ratio of elements in order to make that compound have the same properties.
For example:
Water is H₂O. Always. There is no alternate water formula.
Sand however, is a mixture, who knows exactly what is in sand, and how much of it is in there.
