Answer:
[tex]pH=8.43[/tex]
Explanation:
Hello there!
In this case, since the reaction between benzoic acid and sodium hydroxide is carried out in a 1:1 mole ratio, it is possible to calculate the moles of sodium benzoate salt that are produced due to the neutralization as show below:
[tex]n_{salt}=0.2mol/L*1L=0.2mol[/tex]
We can assume that the volume of benzoic acid is 1 L and therefore the used volume of NaOH is:
[tex]V_{NaOH}=\frac{0.200M*1L}{0.060M}=3.33L[/tex]
Which means that the total final volume is 4.33 L and the concentration of the resulting basic salt is:
[tex][salt]=\frac{0.2mol}{4.33L}=0.046M[/tex]
Next, since the salt is C6H5COONa, we can see it is ionized in Na+ cations and C6H5COO- anions, but just the latter is able to react with the water in the solution in order to undergo the following reaction:
[tex]C_6H_5COO^-+H_2O\rightleftharpoons C_6H_5COOH+OH^-[/tex]
Whose equilibrium expression, it terms of Kb, due to the release of OH- ions, is:
[tex]Kb=\frac{[C6H5COOH][OH^-]}{[C6H5COO^-]}[/tex]
And can be written in terms of x, Kw and Ka:
[tex]\frac{Kw}{Ka} =\frac{x*x}{0.046M-x} \\\\\frac{1x10^{-14}}{6.3x10^{-5}}=1.59x10^{-10}= \frac{x^2}{0.046M-x}[/tex]
And because Kb<<<<<1 we can neglect the x on the bottom to get:
[tex]1.59x10^{-10}= \frac{x^2}{0.046M}[/tex]
Whereas x is computed as follows:
[tex]x=\sqrt{1.59x10^{-10}*{0.046M} =2.7x10^{-6}M[/tex]
Which is actually equal to the concentration of OH- ions so that we can calculate the pOH prior to the pH:
[tex]pOH=-log(2.7x10^{-6})=5.57[/tex]
And therefore the pH as shown below:
[tex]pH=14-5.57\\\\pH=8.43[/tex]
Which makes sense since this sodium benzoate is a basic salt.
Regards!
A scientist wants to test the effectiveness of a medicine in treating
headaches. He puts the medicine into cookies and then tells his subjects to
lie down and have a cookie when they have a headache. He asks them to give
him feedback about how well these relaxation techniques work to cure their
headaches. What rule of ethics does this experiment break?
O A. The subjects are not informed that they are taking a medicine.
B. It is likely to harm his subjects.
C. The scientist is taking the work of others by reviewing the
subjects' feedback.
D. It is testing more than one variable at the same time.
What is the half-life of a radioisotope if a 20 g sample becomes 5 g after 2 days?
Answer: A- 1 day
Explanation: I really hope that helped. BYE!!
1 day is the half-life of a radioisotope if a 20 g sample becomes 5 g after 2 days
Please answer all of the examples below!
Answer:
The first one is balanced. The second one is not.
Explanation:
The first one is balanced because there are the same amount of elements on the reactant side as there are on the product side. The second one is not balanced because there are not the same amount of elements on the reactant side as there are on the product side. Therefore, it is not balanced
More Detailed: first example
Reactant side (left of arrow)
H: 2
C: 1
O: 3
Product side (right of arrow)
H: 2
C: 1
O: 3
More detailed: second example
Reactant side:
Na: 1
O: 1
H: 1
C: 1
Product side:
Na: 2
O: 4
H: 2
C: 1
the variables needed to balance this equation is 2,1, 1, 1.
Is this an example of physical or chemical weathering?
chemical
physical
Answer:
Physical
Explanation:
because the erosion of the canyon did not change any of the chemical attributes of the rock it only changed the appearance. it may have changed the color which is an example of chemical properties but in this case, it is physical. But in other cases, you would refer to this type of weathering as mechanical weathering.
Answer:
it physical
Explanation:
because it moving
Hydrocarbons separated by fractional distillation of petroleum can be cracked to make
useful shorter chain products.
Which substance is not a product of the cracking of propane, M, 44?
A C.Hg
B C2H4
C C3H6
DH2
Q Zoom image
Answer:
{ x R X
Daraaranh
a
o
זחו
Answer:
c.hg cannot be cracked for fractional distillation as there is only one of each
Explanation:
when you rub your sock on carpet then touch a door what happens? what are the charges doing?
Ca(NO3)2 wht is the mass
Answer:
164.088 g/mol
Explanation: hope this helps
Answer:
Calcium nitrate
Explanation:
164.088 g/mol
give me the brainliest plss
What are the 2 common uses for Polonium?
How is a water wave similar to a pendulum?
Answer:
side to side?
Explanation:
There are 1 1/2 times the amount of
we need on the planet today
A gas occupies 12.3 L at a temperature of 40.0 K. What is the volume when the temperature is increased to 60.0 K?
Answer:
the volume is 18.45 L
Explanation:
The computation of the volume when the temperature is increased to 60.0 K is shown below:
Since the gas occupied 12.3 L at a temperature of 40.0 k
And, the volume when the new temperature is 60.0 k
So, the volume is
= 60.0 k × 12.3 L ÷ 40.0 k
= 18.45 L
hence, the volume is 18.45 L
Como se explica o fato de o diamante e o grafite serem formados pelo mesmo elemento, o carbono, e serem materiais completamente diferentes?
Answer:
Ver explicacion
Explanation:
La capacidad de un elemento de existir en diferentes formas en el mismo estado físico se conoce como alotropía.
No es solo el carbono el que exhibe alotropía. También se sabe que el azufre y el fósforo exhiben alotropía.
Hay dos alótropos cristalinos de azufre; grafito y diamante. El grafito y el diamante difieren en la disposición de los átomos de carbono y la naturaleza de los enlaces entre los átomos de carbono en ambas sustancias.
Por lo tanto, el grafito y el diamante tienen propiedades físicas y químicas observadas completamente diferentes debido a las diferencias en la disposición de los átomos de carbono en cada sustancia, así como a las diferencias en la naturaleza de los enlaces entre los átomos de carbono en ambas sustancias.
What mass of ethanol can you boil with 9986 J if the heat of vaporization is 854 J/g?
Answer:
51,069.2 J
Explanation:
Use the heat of vaporization formula:
q=m⋅Hv
The heat of vaporization of ethanol is 854 J/g (given in the question), which means that it takes 854 joules of energy to vaporize one gram of ethanol.
Since we have 59.8 grams of ethanol, plug 59.8 into the formula and multiply by 854.
q = (59.8) (854)
q= 51069.2 J
hope this helped somehow
HELP PLEASE 40.0 grams of salt are dissolved in 100. grams of water. The solution is how many grams?
Answer:
The mass of the solution is 140 grams.
Explanation:
The mass of the solution is given by the sum of the solute's mass and the solvent's mass:
[tex] m_{sol} = m_{ste} + m_{svt} [/tex]
Where:
[tex] m_{sol} [/tex]: is the mass of the solution
[tex]m_{ste}[/tex]: is the mass of the solute
[tex]m_{svt} [/tex]: is the mass of the solvent
The solute is the salt (40.0 g) and the solvent is the water (100 g), so:
[tex] m_{sol} = m_{ste} + m_{svt} = 40 g + 100 g = 140 g [/tex]
Therefore, the mass of the solution is 140 grams.
I hope it helps you!
HELP ME PLEASE WILL GIVE BRAINLY NO BAD ANSWERS
Answer:
7.17
Explanation:
convert 5.50g to moles of salicylic acid. Then use mole ratios and convert the moles of salicylic acid to moles of Asprin(mole ratio is 1:1). Then convert the moles to grams using the molar mass of asprin.
A sample of aluminum has a density of 2.7g/cm3. the mass of the aluminum is 11g. what would be the volume of the aluminum sample?
A sample of aluminum has a density of 2.7g/cm³. The mass of the aluminum is 11g. What would be the volume of the aluminum sample ?
Answer:-Given:-Density of a sample of aluminium is 2.7g/cm³.
The mass of the aluminium is 11g.
To Find:-The volume of the aluminium sample.
Solution:-We know,
[tex] { \boxed{\bf{\rm \red {Volume \: = \frac{Mass}{Density}}}}} [/tex]
So, [tex] \bf Volume \: = \frac{11}{2.7} [/tex]
[tex] \bf Volume \: = \: 4.07 \: cm³ [/tex]The volume of the aluminium sample is 4.07 cm³. [Answer]what is the physical change of a liquid to a solid by the removal of heat?
pls help help help!
i give 20 points
pls
Answer:
His name is Harold
Explanation:
Speed is the rate of change of position expressed as _____ traveled per unit of time. A. direction B. meter C. displacement D. distance
Answer. Speed is the rate of change of position expressed as distance travelled per unit of time
give brainliest if right
Answer:
distance
Explanation:
The half life of tritium is 12.3 years. How much sample will remain if you start with 425g of tritium that is found after 4 half lives?
Answer:
26.56g
Explanation:
The half life of an isotope decay is the time transcurred when the initial amount of the isotope decays to the half of its amount.
For the problem, when 1 half life transcur, the sample has a mass of:
425g / 2 = 212.5g
When 2 half lives transcur:
212.5g / 2 = 106.25g
3 half lives:
106.25/2 = 53.13g
And the amount that is found after 4 half lives is:
53.13/2 =
26.56gWhat are the products of the following neutralization reaction? (No need to balance)
H3PO4 + Ba(OH)2 --> ??? + ???
A.)H2O + Ba3(PO4)2
B.)H30+ + BaPO4
C.)H30+ + Ba3(PO4)2
D.)H2O + BaPO4
H3PO4 + Ba(OH)2 --> Ba3(PO4)2 + H2O
so, (A) H2O + Ba3(PO4)2 is your answer.
why would a farmer add calcium hydroxide to his soil
A student combines 20.0 grams of hydrogen and 20.0 grams of oxygen in a reaction. According to the law of conservation of mass, how many grams of water should be produced?
A)20.0grams B)40.0grams C)30.0grams D)10.0grams
Answer:
A)20.0grams
Explanation:
Answer:
10
Explanation:
If a response is towards a stimulus it's described as _______; if a response is away from the stimulus it's described as _____.
Answer: Positive tropism, negative tropism
Explanation:
Stimulus can be define as external and internal agent which generate a response in an organism. If the growth and action is towards the stimulus it is called as positive tropism. If the growth and action is away from the stimulus it is called as negative tropism. Example, the growth of the stem towards the sunlight is called positive tropism whereas the growth of the root away from the sunlight is called negative tropism. Here, sunlight is the stimulus.
How many liters of water vapor is produced when 33.4 moles of gaseous ammonia is reacted in the following reaction? Hint: Convert to moles first
Answer:
4 liters I think actually hold on
water will boil when...
Answer:
C
Explanation:
Cuántos gramos de cloruro de magnesio se pueden obtener si se hacen reaccionar 354,9g de cloruro de titanio (IV) y 285g de magnesio puro, Recuerde que como productos obtiene titanio y cloruro de magnesio.
a. escriba la ecuación balanceada
b. determine el reactivo limite
c. La cantidad de reactivo en exceso
Answer:
sorry I dont speak Spanish
Which choices are uses of electrical energy?
Choose all that apply.
A. creates useful gases
B. supplies energy for heat
C. provides power to lights
D. creates a magnetic force
Answer:
option A,B and C.
are the options I chose.
The electrical devices include those that are needed to power appliances and those that are used in daily life. In order to make things operational, they need power or energy.
Electrical energy is taken from the movement of electronically charged particles. These when collide produce energy that can be used for heating, lighting, etc.Hence the option C is correct.
Learn more about the choices are uses of electrical energy.
brainly.com/question/20580527
GUYS PLEASE HELP ME
giving brainliest
2
Hope this helps :)
...............................
How much water should be added to 5.00 g of KCl to prepare a 0.500 m
solution? *
Molality = moles of solute
Kg of solvent
100 g
38g
500 g
134 g
Other
Answer:133.4
c
m
3
Explanation: Explanation:
Molarity is number of moles of solute divided by number of litres of solution.
M
=
n
V
Rearrange for V to give
V
=
n
M
Number of moles of KCl is the mass divided by the molar mass of KCl which is 75.5 g/mol, so (5/75.5) = 0.0667 moles.
Now plug in the numbers:
V
=
n
m
=
0.0667
0.5
=
0.1334
litres
So you need to add 0.1334 litres of 133.4
c
m
3
of water.
(NB: symbol for molarity is upper case M. m is metres).
