Answer:
a. pH → 8.12
b. pH → 10.55
c. pH → 8.38
Explanation:
In this excersise, the first two salts come from a strong base and a weak acid, so the anion will make hydrolisis that can help us, to determine pH.
The NH₄ClO₄ comes from a weak acid and a weak base. This is an special case.
a. KNO₂ → K⁻ + NO₂⁻
NO₂⁻ + H₂O ⇄ HNO₃ + OH⁻ Kb = 1.41×10⁻¹¹
Kb = x² / (0.12 - x)
We can avoid the x in denominator because Kb it is a very low value. This expression is reduced to:
[OH⁻] = √(Kb . 0.12)
[OH⁻] = √(1.41×10⁻¹¹ . 0.12) = 1.30×10⁻⁶ M
- log [OH⁻] = pOH → - log 1.30×10⁻⁶ = 5.88
14 - pOH = pH → 14 - 5.88 = 8.12
b. NaOCl → Na⁻ + OCl⁻
OCl⁻ + H₂O ⇄ HClO + OH⁻ Kb = 3.33×10⁻⁷
The same as before, we avoid the x in denominator because Kb it is a very low value.
[OH⁻] = √(Kb . 0.37)
[OH⁻] = √(3.33×10⁻⁷ . 0.37)
[OH⁻] = 3.51×10⁻⁴ M
- log 3.51×10⁻⁴ = 3.45 → pOH
14 - 3.45 = 10.55 → pH
c. NH₄ClO₄ → NH₄⁺ + ClO⁴⁻
Both ions can make hydrolisis in water. Ammonium can give ammonia and the hypochlorite makes hypochlorous acid.
NH₄⁺ + H₂O ⇄ NH₃ + H₃O⁺ Ka = 5.7×10⁻¹⁰
OCl⁻ + H₂O ⇄ HClO + OH⁻ Kb = 3.33×10⁻⁷
The reduced expression to calculate pH for this sort of salts, is to make the square root of the product between the Ka constant.
As we have Kb for the HClO, we need to determine the Ka
Kw = Ka . Kb → Kw/Kb = Ka → 1×10⁻¹⁴ / 3.33×10⁻⁷ = 3×10⁻⁸
[H₃O⁺] = √(5.7×10⁻¹⁰ . 3×10⁻⁸) = 4.14×10⁻⁹ M
- log [H₃O⁺] = pH → - log 4.14×10⁻⁹ = 8.38
As per the calculations of the pH the solutions of 0.12 M KNO2 and 0.37 M NaOCl and the 0.39 M NH4ClO4 web assign have been made with a significant check on the figures.
Thus the answer for the first is pH → 8.12 and that of second calculation is pH → 10.55 and the last id pH → 8.38.Learn more about the Calculate the pH of each of the following solutions.
brainly.com/question/9465562.
plz help this was due yesterday butttttt i didn’t want to do it...
Answer:
I don't get what you want me to do cause n Explano questions showing ation:
A bee buzzes inside a flower to drink some nectar. While there it touches the stamen. Later the bee goes to another flower and comes into contact with the flower's pistil. Which process of reproduction is this helping with?
QUESTION
A bee buzzes inside a flower to drink some nectar. While there it touches the stamen. Later the bee goes to another flower and comes into contact with the flower's pistil. Which process of reproduction is this helping with?
ANSWER
The bee is helping in pollination which is an important event in case of sexual reproduction in flowering plants.
Pollination is a part of pre-fertilisation ( gamete transfer ).
Pollination by insects ( most commonly bees ) is known as Entamophily
What are some ways that use physics in your everyday life?
Answer:
Roasting s'mores over a fire.
Ironing the wrinkles out of my shirts.
Wet clothes are dried with the hot air of the dryer.
Small speakers in your headphones use electricity and moving magnets to create sound waves.
Explanation:
PLEASE HELP ME, EMERGENCY SITUATION (50 points)
207.86 grams of uranium (V) hydroxide reacts with 155.78 grams of thorium disulfate, which is the limiting reactant? You must prove your answer by showing the necessary work and explaining your answer choice.
Answer:
Thorium disulfate
Explanation:
Thorium also forms insoluble compounds with fluoride, sulfate, ... hydroxide from solutions of pH 3.6 or above. ... rate should be about 2.5 g/min, and the reaction tube temperature ... thenoyl group decreases the solubility of the reagent in the aqueous
what's a vacuum exactly
Answer:
Vacuum: space in which there is no matter or in which the pressure is so low that any particles in the space do not affect any processes being carried on there It is a condition well below normal atmospheric pressure and is measured in units of pressure (the pascal).-the internet gave me this answer so..
Explanation:
hope this helps :)
- What is the percent yield if your actual yield is 39.78g and your theoretical
yield was 47.84 g?
1. Which of the following elements have atoms with a full shell of
valence electrons (1 point)
a. Lithium
b. Oxygen
c. Hydrogen
d. Neon
Answer:
The answer is neon.
Explanation:
Hope this helped Mark BRAINLEST!!!
This is an example of which type of short-term human-induced environmental change?
Answer:
The short term human induced environmental changes are pollution and deforestation. The term deforestation can be defined as the cutting down of trees in huge amount. The reason can be cutting down of trees for human settlement. Pollution can be defined as the undesirable in the environment.
Q1 - How would you balance the following equation: N₂ + O₂ N₂O₅
A: N₂ + 5 O₂ N₂O₅
B: 2 N₂ + 5 O₂ 2 N₂O₅
C: N₂ + 5 O₂ N₂2O₅
D: N₂ + O₂ N₂O₅ (already balanced)
Q2 - In the reaction, HCl + NaOH NaCl + H₂O, what is/are the reactant(s)?
A: HCl only
B: HCl and NaOH
C: NaCl only
D: HCl and NaCl
nswer:
For Q1 its B!
Explanation:
cuz I'm smart dw.
question above in picture
PLEASE HELP!
The chemical formula of a compound provides information about the elements present in the compound and their ____
ratios. A) grams B) ratio C) mole D) empirical
Answer:
C. Mole
Explanation:
Chemical formula deals with mole number
Each time a person walks into a room and tums on a light, a change in energy occurs. What is this change in energy?
electrical energy is converted into light energy
kinetic energy is converted and the potential energy
light energy is converted in mechanical energy
Chemical energy is converted into potential energy
3) Which element has the lowest electronegativity value?
A) F
B) Fr
C) Cr
D) Cl
Answer:
ur mom jk i would say fr
Explanation:
Type of introduction
Answer:
Five Types of Introductions.
“Inquisitive” Explain why your subject is important, curious, or interesting.
“Paradoxical” Explain what aspects of your subject seem improbable. ...
“Corrective” Explain how your subject has been misunderstood or misrepresented by others. ...
How much force is required to accelerate a 22 kg mass at 6 m/s2?s
Answer:
F=132k.gm/s^2Explanation:
F=m×af=22k.g×6m/s^2f=132k.gm/s^2Consider the equation for the formation of a kidney stone.
2Na3 PO4 (aq) + 3CaCl2 (aq) =
Ca3(PO4)2 (s) + 6NaCl (aq)
Is each reactant bonded ionically or covalently?
How do you know?
Answer:
Ionically, because they are ionic compounds
A hydrochloric acid solution contains 36 percent HCl by mass. Calculate its
molality
Determine the moles of chlorine needed to react with 38.9 of iron (III) chloride.
2 Fe+3 CI, - 2 Feci
Answer: 0.360 moles
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} FeCl_3=\frac{38.9g}{162.2g/mol}=0.240moles[/tex]
The balanced chemical reaction is:
[tex]2Fe+3Cl_2\rightarrow 2FeCl_3[/tex]
According to stoichiometry :
2 moles of require = 3 moles of
Thus 0.240 moles of [tex]FeCl_3[/tex] will require=[tex]\frac{3}{2}\times 0.240=0.360moles[/tex] of [tex]Cl_2[/tex]
Thus 0.360 moles of chlorine needed to react to produce 38.9 of iron (III) chloride.
The overall electrical charge on a stable element is_____
Answer: the answer is 0
Explanation:A stable atom has a net charge of 0. In other words, it has an equal number of protons and electrons. The positive protons cancel out the negative electrons.
If you can solve both
Will mark brainly
ASAP
Answer:
The main function sis the 2nd one and the substance provides the first 1.
Explanation:
Hope you finish the rest on your own, have fun!
Between what time interval was the object moving the slowest?
Between what time interval was the object moving the fastest
Answer:
from 1 to 2 hour the object was moving the slowestfrom 4 to 5 hours the object was moving the fastestIn which ways are evaporation and condensation similar?
Both cause decrease in air temperature
Both cause increase in air temperature
Both are caused by the warming of the atmosphere
Both are caused by changes in heat energy
Answer:
Both are caused by changes in heat energy
Explanation:
When air gets hotter water will evaporate, when air gets cooler water will condensate.
what are particles that differ in number between isotopes
Answer:
Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons and electrons. The difference in the number of neutrons between the various isotopes of an element means that the various isotopes have different masses.
The reaction between sodium and chlorine that forms table salt is shown
_Na(s) + Cl2 (g) → _NaCl (3)
What coefficient should be added to the blanks to balance the equation?
А.
2
В.
1
2.
2
Answer: 2 Na (s) + Cl(g) -> 2 NaCl (s)
Explanation:
A tank containing 5.00 L of nitrogen at 75.0 atm pressure and 28.0 C is left standing in sunlight. Its temperature rises to 50.0C. What is the pressure at this higher temperature?
Answer:
80.5 atm
Explanation:
First of all, we convert 28.0 °C and 50.0 °C into K:
28.0 + 273.16 = 301.16 K50.0 + 273.16 = 323.16 KTo answer this problem we'll use Gay-Lussac's Law, which states that:
T₁*P₂=T₂*P₁In this case:
T₁ = 301.16 KP₂ = ?T₂ = 323.16 KP₁ = 75.0 atmWe put the data:
301.16 K * P₂ = 323.16 K * 75.0 atmAnd solve for P₂:
P₂ = 80.5 atmThus, the correct answer is 80.5 atm.
How many valence electrons are there in Se atom?
Answer:
4 valence electrons
Despite the fact that the word silicon has a ubiquitous affiliation with all things electronic, Si itself is not a good electrical conductor. It has 4 valence electrons, meaning that filling its outer shell it can form a very strong lattice with 4 neighboring Si atoms-with no un-bonded electrons remaining
Answer:
The numer of valence electrons is defined as the number of electrons present in the outer most shell of the atom.So, in the case if selenium, there are 6.
What is the answer?
Which of your recipes was the best?
Trial 1
Trial 2
Trial 3
Why is this your best recipe? What criteria did you meet?
Answer:
trial 1
Explanation:
trust
What are some ways the stars in the photo could be grouped or classified
How many grams of potassium chloride are in 4.25 x 1023 molecules?
Do a quick conversion: 1 moles Potassium Chloride = 74.5513 gram using the molecular weight calculator and the molar mass of KCl.