The pH of the solution after adding 0.150 moles of solid LiF is 3.84
<u>Explanation:</u>
We have the chemical equation,
HF (aq)+NaOH(aq)->NaF(aq)+H2O
To find how many moles have been used in this
c= n/V=> n= c.V
nHF=0.250 M⋅1.5 L=0.375 moles HF
Simillarly
nF=0.250 M⋅1.5 L=0.375 moles F
nHF=0.375 moles - 0.250 moles=0.125 moles
nF=0.375 moles+0.250 moles=0.625 moles
[HF]=0.125 moles/1.5 L=0.0834 M
[F−]=0.625 moles/1.5 L=0.4167 M
To determine the problem using the Henderson - Hasselbalch equation
pH=pKa+log ([conjugate base/[weak acid])
Find the value of Ka
pKa=−log(Ka)
pH=−log(Ka) +log([F−]/[HF]
pH= -log(3.5 x 10 ^4)+log(0.4167 M/0.0834 M)
pH=-log(3.5 x 10 ^4)+log(4.996)
pH= -4.54+0.698
pH=-(-3.84)
pH=3.84
The pH of the solution after adding 0.150 moles of solid LiF is 3.84
Answer:
40.4 kJ
Explanation:
Step 1: Given data
- Heat of sublimation of CO₂ (ΔH°sub): 32.3 kJ/mol
Step 2: Calculate the moles corresponding to 55.0 g of CO₂
The molar mass of CO₂ is 44.01 g/mol.
n = 55.0 g × 1 mol/44.01 g = 1.25 mol
Step 3: Calculate the heat (Q) required to sublimate 1.25 moles of CO₂
We will use the following expression.
Q = n × ΔH°sub
Q = 1.25 mol × 32.3 kJ/mol = 40.4 kJ
Hello the term for weight is newton
hope this helped.
Cody
Answer:
The condor has a wing span of 10 feet
Explanation:
This can be solved by a simple rule of three
In a rule of three problem, the first step is identifying the measures and how they are related, if their relationship is direct of inverse.
When the relationship between the measures is direct, as the value of one measure increases, the value of the other measure is going to increase too. In this case, the rule of three is a cross multiplication.
When the relationship between the measures is inverse, as the value of one measure increases, the value of the other measure will decrease. In this case, the rule of three is a line multiplication.
In this problem, our measures are the wing span of the condon in meters and the wing span of the condor is feet. As the value of one of these measures increases, the other is going to increase too.
We know that 1m has 3.281 feet,
So we have the following rule of three:
1m - 3.281 feet
3.05m - x feet
x = 3.821*3.05
x = 10 feet
The condor has a wing span of 10 feet
Flammability
Hope it helps!
