Explanation:
Physical Change is a type of change where by no new chemical substance is formed. Physical changes are reversible. whilst Chemical change is a change where new chemical substance is always formed. Chemical changes are usually irreversible.
Examples of Physical Change include;
Melting of Ice
Melting of Candle
Grinding of chalk
Magnetization of Iron
Examples of Chemical Change includes;
Cooking of food
Rusting of Iron
Burning of Charcoal
In another experiment, the student titrated 50.0mL of 0.100MHC2H3O2 with 0.100MNaOH(aq) . Calculate the pH of the solution at the equivalence point.
pH=8.87
Further explanationReaction
C₂H₄O₂+NaOH⇒CH₃COONa+H₂O
at the equivalence point = mol C₂H₄O₂= mol NaOH
mol C₂H₄O₂ : 50 x 0.1 = 0.5 mlmol=5.10⁻⁴ mol
The two reactants have completely reacted, and there is only salt(CH₃COONa) and water(H₂O), there will be hydrolysis
For acids from weak acids and strong bases (the solution is alkaline) then the calculation:
[tex]\tt [OH^-]=\sqrt{\dfrac{Kw}{Ka}\times M }[/tex]
M=anion concentration=CH₃COO⁻
Ka=acid constant(for CH₃COOH,Ka=1.8.10⁻⁵)
[tex]\tt [OH^-]=\sqrt{\dfrac{10^{-14}}{1.8.10^{-5}}\times 0.1 }[/tex]
[tex]\tt [OH^-]=\sqrt{5.6.10^{-11}}=7.483\times 10^{-6}[/tex]
pOH=6-log 7.483=5.13
pH= 14 - 5.13=8.87
The pH of the solution is the negative log [H] concentration. The pH of the given solution is 8.87 at the equivalence point.
pH:The given Reaction is:
C₂H₄O₂+ NaOH ⇒ CH₃COON + H₂O
The pH of the solution can be calculated by,
[tex]\bold{pH = 14 - pOH}[/tex]................1
So first, calculate for pOH
[tex]\bold {pOH = \sqrt {\dfrac {Kw}{Ka} \times M}}[/tex]
Where,
Ka - dissociatioon constant = 50 x 0.1 = 0.5 ml = 5x10⁻⁴ mol
Kw - concentaion water ionic products = [tex]\bold {10^{-14}}[/tex]
M - anion concentration( CH₃COO⁻) = 0.1 M
Put the values in the formula,
[tex]\bold {pOH = \sqrt {\dfrac {\bold {10^{-14}}}{5\times 10^{-4} mol} \times 0.1}}\\\\\bold {pOH = 7.483 \times 10^{-6}}[/tex]
Since the pOH is the negative log of [OH⁻] concentration,
pOH = 6 -ln 7.483
pOH = 5.13
Put the value of pOH in the first equation,
pH= 14 - 5.13
pH = 8.87
Therefore, the pH of the given solution is 8.87 at the equivalence point.
Learn more about pH:
https://brainly.com/question/491373
please answer these questions!
Explanation:
1)
Equation -
Propane + oxygen → carbon dioxide + water
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
Here,
Products are -
Carbon dioxide (CO₂) Water (H₂O)2)
Equation -
AgNO₃ (aq.) + NaCl (s) → AgCl ↓ + NaNO₃ (aq.)
Double Displacement reactionCan you guys help please?
Answer:
its false
Explanation:
is this a joke. I honestly don't know why you would need help.
The mass ratio of hydrogen to oxygen in water (formula H20) is 0.126 g hydrogen for every 1 g of oxygen. In another compound of hydrogen and oxygen called hydrogen peroxide, the mass ratio of hydrogen to oxygen is 0.063 g hydrogen for every 1 g of oxygen. What is a possible formula of hydrogen peroxide?
Answer: H2O2
Explanation:
How many protons are in the nucleus of one atom of neon based on this information found in the Periodic Table?
Answer:
10 protons
Explanation:
The atomic number of an element is equal to the number of protons of the element. The atomic number of neon is 10. Therefore, neon contains 10 protons.
10 protons are in the nucleus of one atom of neon based on this information found in the Periodic Table.
What is periodic table ?The chemical elements are arranged in rows and columns in the periodic table, sometimes referred to as the periodic table of the elements. It is frequently used in physics, chemistry, and other disciplines and is frequently regarded as a symbol of chemistry.
The elements are organized in what is known as the periodic table. Columns and rows are used to organize the table. The horizontal rows are referred to as "periods," while the vertical columns are known as "groups."
Thus, The atomic number of an element is similar to the number of protons of the element. The atomic number of an element neon is 10. So, neon contains 10 protons.
To learn more about the periodic table, follow the link;
https://brainly.com/question/11155928
#SPJ2
A teacher performs a flame test lab experiment for various compounds. During the lab, the teacher mislabels one of the solutions. She needs to identify the unknown sample. Explain how the teacher can identify the unknown sample.
Answer: By performing the flame test
Explanation:
The flame test can be performed by the teacher to visually identify the substance in the solution. The metals give a characteristic color on burning. The heat of the flame causes the excitation of the electrons present in the metal ions this leads to release of energy along with the emission of visible wavelength of light. This visible light can be observed by human eye. For example, the copper produces the blue color in flame, barium gives green flame, and sodium gives yellow flame.
A block with a volume of 24 cm3 has a mass of 1200 g. What is the density of this block
Answer:
The answer is 0.02 g/cm³Explanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question we have
[tex]density = \frac{24}{1200} = \frac{1}{50} \\ [/tex]
We have the final answer as
0.02 g/cm³Hope this helps you
A bond in which two atoms share a pair of electrons is a ionic bond or covalent bond or metallic bond?
Answer:
Covalent
Explanation:
Ionic gives or takes electrons
Metallic isn't really a "type" of bond
What are some of the challenges and reasons for
sending people back to the Moon by 2024?
Answer: Prob to see if anything new has came or has happened
Explanation:
Answer:
NASA Publishes Artemis Plan to Land First Woman, Next Man on Moon in 2024. ... We're going back to the Moon for scientific discovery, economic benefits, and inspiration for a new a generation of explorers. As we build up a sustainable presence, we're also building momentum toward those first human steps on the Red Planet.
Explanation:
need some help with this
Answer:
Speed
Explanation:
Am i gay?
I cant tell so i may need a third party to tell me whether i like men or not
Answer:
ok
Explanation: whatever you think
What do the colors represent?
Answer:
Dark Blue: Symbolizes integrity, knowledge, power, and seriousness. Blue: Peace, tranquility, cold, calm, stability, harmony, unity, trust, truth, confidence, conservatism, security, cleanliness, order, loyalty, sky, water, technology, depression, appetite suppressant.
How does solubility impact the temperature?
Answer:
For many solids dissolved in liquid water, the solubility increases with temperature. The increase in kinetic energy that comes with higher temperatures allows the solvent molecules to more effectively break apart the solute molecules that are held together by intermolecular attractions.
Explanation:
Make sure to edit so you do get copy-writed
answer asap correctly for brainleist and pls give the right answer thx!
A
Explanation:
B is wrong because it talks about speed, C is wrong because it talks about direction, and D is wrong because it talks about the amount of tilt. A is correct because it's the only one that talks about the time of the orbit and the time of orbit determines the length of a year. :)
Ung number three po plssssssssssss.
Answer:
For #3 I believe it's A
Explanation:
It can't be changed INTO a solid because it already is one.
Hope this helps!
Josh is washing glasses with soap and water. He is afraid to
carry the glasses because they are slippery. What might he find in the
kitchen that he could use to keep the glasses from being slippery? Explain.
Josh is washing glasses with soap and water. He is afraid to carry the glasses because they are slippery. Josh could dry them with a towel to keep the glasses from being slippery.
What are glasses ?Glasses are visual eyewear that have lenses fixed in a frame that holds them in front of a person's eyes. The frame often has a bridge over the nose and arms that rest over the ears. Glasses are also known as eyeglasses or spectacles.
The term "glasses" likely originated from the word "spyglass," which was originally used to describe "a pair of eyeglasses" that had to be held up to the eyes in order to be fully effective.
Eyeglasses, often known as glasses or spectacles, are lenses that are mounted in frames and worn in front of the eyes to improve vision or to correct astigmatism, myopia, or hyperopia.
Thus, Josh could dry them with a towel to keep the glasses from being slippery.
To learn more about glasses, follow the link;
https://brainly.com/question/9399000
#SPJ5
Plants and animals can build up or break down rock by increasing weathering, erosion, and
deposition. true or false
Answer:
false
Explanation:
Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering.
Use the reaction given below to solve the problem that follows: Calculate the mass in grams of aluminum metal required to react with 115 g of oxygen
gas
grams Al
4 Al + 3O2 --> 2 Al2O3
**Your answer should be written as XXX
Answer:
4Al + 3O2 --> Al2O3
Step 1; fi
Please hurry i really need it fast
Phillip throws a basketball up in the air and through a hoop. Because the ball is acted on by the force of gravity, the ball will —
Answer:
Fal down to the flour
Explanation:
Because of gravity their is weight that weight keeps us down to earth everything has weight even a leaf not only weight but the atmosphere is like a wall that keeps us safe from all the stuff in space.
Rahul was given iron filings and sulphur powder. He prepared a compound of iron sulphide by heating the components in a china dish. What would be his observation if he adds a few drops of dilute sulphuric acid into the compound?
Answer:
A gas with a rotten egg smell is evolved
Explanation:
When iron fillings and sulphur were heated in the vessel, the following chemical reaction took place;
Fe(s) + S(s) -----> FeS(s)
This is a direct combination reaction.
Subsequently, when dilute H2SO4 is added, the following reaction takes place;
FeS(s) + H2SO4(aq) ------> FeSO4(aq) + H2S(g)
He immediately observes the evolution of a gas with a rotten egg smell.
why is the chemical reaction between nitric acid and sodium hydroxide called a neutralization reaction?
Answer:
Because nitric acid is acidic in nature and sodium hydroxide is basic in nature so when acid and base react they become neutral.
What is an inorganic chemical?
A. A chemical that contains carbon atoms
B. A chemical that does not take part in reactions
C.A chemical that makes up living things
D.A chemical that is not from living things
I'd appreciate anyone's help
Answer:
D.A chemical that is not from living things
im in the middle of a chem test and i literally have no clue what is happening
Answer:
No question so I'm just taking the points
The rock was white and black speckled with a density of 2.6 g/mL. Physical or chemical property?
Answer:
Chemical
Explanation:
Complete the sentence by using the drop-down menus
to choose the words that describe the image most
accurately
To make an omelet, first
the egg and then let
the insides slide
into the bowl.
Answer:
1st one: crack
2nd: carefully
Explanation:
Answer:
Crack and then carefully
Explanation:
I just did it in edgen 2020
The atomic mass unit is based on which element?
Carbon-12
Carbon-12 is the reference for all atomic mass calculations. An atomic mass unit is defined as a mass equal to one twelfth the mass of an atom of carbon-12.
The length breadth and thickness of a brick is 18cm 8 cm and 5cm respictively find the area of the widest part of rhe brick
Answer:
144cm²
Explanation:
Given dimensions:
Length x breadth x thickness
18cm x 8cm x 5cm
The widest part of this figure will be the face containing the length and the breadth.
The breadth is the width of the figure;
Area of the widest part = length x breadth = 18cm x 8cm = 144cm
The area of the widest part of the figure is 144cm²
Heeeelp ill give brainlist
Which of the following is an oxidation-reduction reaction? ZnS(s) + 2O2(g) ZnSO4(s) CaO(s) + H2O(l) Ca(OH)2(s) 6Li2O(s) + P4O10(g) 4Li3PO4(s) SO2(g) + H2O(l) H2SO3(aq)
ZnS(s) + 2O₂(g) ⇒ZnSO₄(s)
Further explanationThe oxidation-reduction reaction or abbreviated as Redox is a chemical reaction in which there is a change in oxidation number
Oxidation is an increase in oxidation number, while reduction is a decrease in oxidation number.
Reaction
ZnS(s) + 2O₂(g) ⇒ZnSO₄(s)
S²⁻ (-2 in ZnS) to S⁺⁶(+6 in ZnSO₄) ⇒ oxidation
O₂(0 in O₂) to O⁻²(-2 in ZnSO₄)⇒ reduction
Answer:
A. ZnS(s) + 2O2(g) Right arrow. ZnSO4(s)
Explanation: