Answer:
42.1 kj
Explanation:
Given data:
Molar heat of vaporization = 3.86×10⁴ j/mol
Mass of ethanol = 50 g
Amount of heat required to convert into gaseous form = ?
Solution:
First of all we will calculate the number of moles of ethanol.
Number of moles = mass/ molar mass
Number of moles = 50.0 g/ 46.07 g/mol
Number of moles = 1.09 mol
H(vap) = number of moles × molar heat of vaporization
H(vap) = 1.09 mol × 3.86×10⁴ j/mol
H(vap) = 4.21×10⁴ j
In Kj:
4.21×10⁴ / 1000 = 42.1 kj
Answer:
A. np and nf
Explanation:
The electron distribution into energy levels or sublevels of atoms can be shown in their sublevel notations. This shows the sequence of filling electrons into the orbitals of the sublevels as guided by some principles such as the Aufbau Principle, Pauli Exclusion Principle, Hund's Rule of Maximum Multiplicity e.t.c
The maximum number of electrons in the orbitals of sublevels are two for s-sublevel(one orbital), six for p-level (three orbitals), ten for d-sublevel (five orbitals), and fourteen for f-sublevel (seven orbitals). This explains that the maximum number of electrons in an orbital is two.
Answer:
2.1056L or 2105.6mL
Explanation:
We'll begin by calculating the number of mole in 10g of Na2CO3. This can be obtained as follow:
Molar mass of Na2CO3 = (23x2) + 12 + (16x3) = 106g/mol
Mass of Na2CO3 = 10g
Mole of Na2CO3 =.?
Mole = mass /molar mass
Mole of Na2CO3 = 10/106
Mole of Na2CO3 = 0.094 mole
Next, we shall determine the number of mole CO2 produced by the reaction of 0.094 mole of Na2CO3. This is illustrated below:
Na2CO3 + 2HCl —> 2NaCl + H2O + CO2
From the balanced equation above,
1 mole of Na2CO3 reacted to produce 1 mole of CO2.
Therefore, 0.094 mole of Na2CO3 will also react to 0.094 mole of CO2.
Next, we shall determine the volume occupied by 0.094 mole of CO2 at STP. This is illustrated below:
1 mole of a gas occupy 22.4L at STP. This implies that 1 mole CO2 occupies 22.4L at STP.
Now, if 1 mole of CO2 occupy 22.4L at STP, then, 0.094 mole of CO2 will occupy = 0.094 x 22.4 = 2.1056L
Therefore, the volume of CO2 produced is 2.1056L or 2105.6mL
Low melting point
Low boiling point
Electric conductor
Percent yield or yield is mathematically defined as:
Yield = Actual amount / Theoretical amount
So to solve the yield, let us first calculate the
theoretical amount of POCl3 produced. The balanced chemical reaction for this
is:
6 PCl5 + P4O10 ---> 10 POCl3
Since P4O10 is stated to be supplied in large amount, then
PCl5 becomes the limiting reactant.
So we calculate for POCl3 based on PCl5. To do this let us
convert the amount into moles: (molar mass PCl5 = 208.24 g/mol)
n PCl5 = 42.66
grams / (208.24 g/mol)
n PCl5 = 0.205 mol
Now based on the
stoichiometric ratio of the reaction:
<span>n POCl3 = 0.205 mol (10
POCl3 / 6 PCl5)
n POCl3 = 0.3414 mol POCl3</span>
Converting to mass (molar
mass POCl3 = 153.33 g/mol)
m POCl3 = 0.3414 mol (153.33 g/mol)
m POCl3 = 52.35 g
Calculating for yield:
Yield = 47.22 g/ 52.35 g
Yield = 0.902
<span>%Yield = 90.2 % (ANSWER)</span>
