Answer:
A- pH = 13.12
B- pH = 12.91
C- pH = 12.71
D- pH = 12.43
E- pH = 11.55
F- pH = 7
G- pH = 2.46
H- pH = 1.88
Explanation:
This is a titration of a strong base with a strong acid. The neutralization reaction is: KOH (aq) + HCl (aq) → H₂O(l) + KCl(aq)
Our pH at the equivalence point is 7, because we have made a neutral salt.
To determine the volume at that point we state the formula for titration:
mmoles of base = mmoles of acid
Volume of base . M of base = Volume of acid . M of acid
50mL . 0.129M = 0.258 M . Volume of acid
Volume of acid = (50mL . 0.129M) / 0.258 M → 25 mL (Point F)
When we add 25 mL of HCl, our pH will be 7.
A- At 0 mL of acid, we only have base.
KOH → K⁺ + OH⁻
[OH⁻] = 0.129 M
To make more easy the operations we will use, mmol.
mol . 1000 = mmoles → mmoles / mL = M
- log 0.129 = 0.889
14 - 0.889 = 13.12
B- In this case we are adding, (7 mL . 0.258M) = 1.81 mmoles of H⁺
Initially we have 0.129 M . 50 mL = 6.45 mmoles of OH⁻
1.81 mmoles of H⁺ will neutralize, the 6.45 mmoles of OH⁻ so:
6.45 mmol - 1.81 = 4.64 mmoles of OH⁻
This mmoles of OH⁻ are not at 50 mL anymore, because our volume has changed. (Now, we have 50 mL of base + 7 mL of acid) = 57 mL of total volume.
[OH⁻] = 4.64 mmoles / 57 mL = 0.0815 M
- log 0.0815 M = 1.09 → pOH
pH = 14 - pOH → 14 - 1.09 = 12.91
C- In this case we add (12.5 mL . 0.258M) = 3.22 mmoles of H⁺
Our initial mmoles of OH⁻ would not change through all the titration.
Then 6.45 mmoles of OH⁻ are neutralized by 3.22 mmoles of H⁺.
6.45 mmoles of OH⁻ - 3.22 mmoles of H⁺ = 3.23 mmoles of OH⁻
Total volume is: 50 mL of base + 12.5 mL = 62.5 mL
[OH⁻] = 3.23 mmol / 62.5 mL = 0.0517 M
- log 0.0517 = 1.29 → pOH
14 - 1.11 = 12.71
D- We add (18 mL . 0.258M) = 4.64 mmoles of H⁺
6.45 mmoles of OH⁻ are neutralized by 4.64 mmoles of H⁺.
6.45 mmoles of OH⁻ - 4.64 mmoles of H⁺ = 1.81 mmoles of OH⁻
Total volume is: 50 mL of base + 18 mL = 68 mL
[OH⁻] = 1.81 mmol / 68 mL = 0.0265 M
- log 0.0265 = 1.57 → pOH
14 - 1.57 = 12.43
E- We add (24 mL . 0.258M) = 6.19 mmoles of H⁺
6.45 mmoles of OH⁻ are neutralized by 6.19 mmoles of H⁺.
6.45 mmoles of OH⁻ - 6.19 mmoles of H⁺ = 0.26 mmoles of OH⁻
Total volume is: 50 mL of base + 24 mL = 74 mL
[OH⁻] = 0.26 mmol / 74 mL = 3.51×10⁻³ M
- log 3.51×10⁻³ = 2.45 → pOH
14 - 2.45 = 11.55
F- This the equivalence point.
mmoles of OH⁻ = mmoles of H⁺
We add (25 mL . 0.258M) = 6.45 mmoles of H⁺
All the OH⁻ are neutralized.
OH⁻ + H⁺ ⇄ H₂O Kw
[OH⁻] = √1×10⁻¹⁴ → 1×10⁻⁷ → pOH = 7
pH → 14 - 7 = 7
G- In this case we have an excess of H⁻
We add (26 mL . 0.258M ) = 6.71 mmoles of H⁺
We neutralized all the OH⁻ but some H⁺ remain after the equilibrium
6.71 mmoles of H⁺ - 6.45 mmoles of OH⁻ = 0.26 mmoles of H⁺
[H⁺] = 0.26 mmol / Total volume
Total volume is: 50 mL + 26 mL → 76 mL
[H⁺] = 0.26 mmol / 76 mL → 3.42×10⁻³ M
- log 3.42×10⁻³ = 2.46 → pH
H- Now we add (29 mL . 0.258M) = 7.48 mmoles of H⁺
We neutralized all the OH⁻ but some H⁺ remain after the equilibrium
7.48 mmoles of H⁺ - 6.45 mmoles of OH⁻ = 1.03 mmoles of protons
Total volume is 50 mL + 29 mL = 79 mL
[H⁺] = 1.03 mmol / 79 mL → 0.0130 M
- log 0.0130 = 1.88 → pH
After equivalence point, pH will be totally acid, because we always have an excess of protons. Before the equivalence point, pH is basic, because we still have OH⁻ and these hydroxides, will be neutralized through the titration, as we add acid.
The pH value is given by 14 less the logarithm of the hydronium ion
concentration or the hydrogen ion concentration in the solution.
Responses (approximate values):
The pH values are;
A) 13.11
B) 12.91
C) 12.71
D) 12.42
E) 11.54
F) 7
G) 2.469
H) 1.884
Which is used to find the pH of the solution?A) Concentration of the KOH = 0.129 M
Amount of HCl added = 0.00 ml
The pH = -log[H⁺] = 14 - pOH
pOH = -log[OH⁻]
Which gives;
pH = 14 - (-log[OH⁻] )
pH = 14 - (-log(0.129)) ≈ 13.11B) Volume of acid added = 7.00 mL = 0.007 L
Concentration of the acid = 0.258 M HCl
Number of moles of acid, H⁺ = 0.007 × 0.258 moles = 0.001806 moles
Number of moles of KOH remaining, OH⁻= 0.05 × 0.129 - 0.001806 = 0.004644
Number of moles of OH⁻ = 0.004644 moles
[tex]Concentration, \ [OH^-] = \dfrac{0.004644 \, moles}{0.05 7 \, L} \approx \mathbf{ 0.0815 \, M}[/tex]
pH of solution = 14 - (-log(0.0815)) ≈ 12.91C) 12.5 mL HCl contains, 0.0125 × 0.258 moles = 0.003225 moles
OH⁻ remaining = 0.05 × 0.129 - 0.003225 = 0.003225 moles
[tex]Concentration \ of \ [OH^-]= \dfrac{0.003225\, moles}{(0.05 + 0.0125) \, L} = \mathbf{0.0516 \, M}[/tex]
pH of solution = 14 - (-log(0.0516)) ≈ 12.71D) 18.0 mL HCl contains, 0.018 × 0.258 moles = 0.004644 moles
OH⁻ remaining = 0.05 × 0.129 - 0.004644 = 0.001806 moles
[tex]Concentration \ of \ [OH^-] = \dfrac{0.001806\, moles}{(0.05 + 0.018) \, L} \approx \mathbf{0.0266\, M}[/tex]
pH of solution = 14 - (-log(0.0266)) ≈ 12.42E) 24.0 mL HCl contains, 0.024 × 0.258 moles = 0.006192 moles
OH⁻ ion remaining = 0.05 × 0.129 - 0.006192 = 0.000258 moles
[tex]Concentration \ of \ [OH^-] = \dfrac{0.000258\, moles}{(0.05 + 0.024) \, L} \approx \mathbf{0.0035\, M}[/tex]
pH of solution = 14 - (-log(0.0035)) ≈ 11.54F) 25.0 mL HCl contains, 0.025 × 0.258 moles = 0.00645 moles
[OH⁻] remaining = 0.05 × 0.129 - 0.00645 = 0 moles
[tex]Concentration \ of \ [OH^-] = \dfrac{0\, moles}{(0.05 + 0.024) \, L} \approx 0\, M[/tex]
Therefore;
Number of moles of KOH = 0, or the solution is neutralized
[OH⁻] = [H⁺]
Which gives;
pH = pOH = 7G) 26.0 mL HCl contains, 0.026 × 0.258 moles = 0.006708 moles
[OH⁻] remaining = 0.05 × 0.129 - 0.006708 = -0.000258 moles
Therefore
Number of moles of H⁺ = 0.000258
[tex]\mathbf{Concentration} \ of \ \mathbf{[H^+] }= \dfrac{0.000258\, moles}{(0.05 + 0.026) \, L} \approx 0.003395\, M[/tex]
pH of solution = (-log(0.003395)) ≈ 2.469H) 29.0 mL HCl contains, 0.029 × 0.258 moles = 0.007482 moles
H⁺ remaining = 0.007482 - 0.05 × 0.129 = 0.001032 moles
Therefore
Number of moles of H⁺ = 0.001032
[tex]Concentration \ of \ [H^+] = \mathbf{ \dfrac{0.001032\, moles}{(0.05 + 0.029) \, L}} \approx 0.01306\, M[/tex]
pH of solution = (-log(0.01306)) ≈ 1.884Learn more about the pH of a solution here:
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The mass of a dust particle would be measured in?
Which of the following is true?
A)If we know that a reaction is an elementary reaction, then we know its rate law.
B)The rate-determining step of a reaction is the rate of the fastest elementary step of its mechanism.
C)Since intermediate compounds can be formed, the chemical equations for the elementary reactions in a multistep mechanism do not always have to add to give the chemical equation of the overall process.
D)In a reaction mechanism, an intermediate is identical to an activated complex.
E)all of these statements are true.
Answer:
If we know that a reaction is an elementary reaction, then we know its rate law.
Explanation:
An elementary reaction is a reaction that takes place in one reactive encounter. This means that the two species interact in a single step to give the products.
If two reactants interact in a single step to yield the products then we can easily deduce the rate law from the reaction equation.
For instance, For the reaction;
2A + B → C
The rate law is
rate = k[A]²[B].
If the reaction is an elementary reaction and the equation of the reaction is balanced, then we can deduce the rate law from the balanced reaction equation.
In an experiment, 20cm^3 of 0.2dm^3 NaOH reacted with 32.0cm^3 of H2SO4 solution. Calculate the concentration of the H2SO4 in a) mol dm^-3 and b) g dm^-3
Answer:
A. 0.0625 moldm¯³
B. 6.125 gdm¯³
Explanation:
We'll begin by writing the balanced equation balance equation for the reaction. This is illustrated below:
2NaOH + H₂SO₄ —> Na₂SO₄ + 2H₂O
From the balanced equation above,
The mole ratio of the acid, H₂SO₄ (nₐ) = 1
The mole ratio of the base, NaOH (n₆) = 2
A. Determination of the concentration of the acid in moldm¯³.
Volume of base, NaOH (V₆) = 20 cm³
Concentration of base, NaOH (C₆) = 0.2 moldm¯³
Volume of acid, H₂SO₄ (Vₐ) = 32 cm³
The mole ratio of the acid, H₂SO₄ (nₐ) = 1
The mole ratio of the base, NaOH (n₆) = 2
Concentration of acid, H₂SO₄ (Cₐ) =?
CₐVₐ / C₆V₆ = nₐ / n₆
Cₐ × 32 / 0.2 × 20 = 1 / 2
Cₐ × 32 / 4 = 1 / 2
Cross multiply
Cₐ × 32 × 2 = 4 × 1
Cₐ × 64 = 4
Divide both side by 64
Cₐ = 4 / 64
Cₐ = 0.0625 moldm¯³
Therefore, concentration of the acid in moldm¯³ is 0.0625 moldm¯³
B. Determination of the concentration of the acid in gdm¯³.
Concentration (moldm¯³) = 0.0625 moldm¯³
Concentration (gdm¯³) =?
Next, we shall determine the molar mass of the acid, H₂SO₄. This can be obtained as follow:
Molar mass of H₂SO₄ = (2×1) + 32 + (4×16)
= 2 + 32 + 98
= 98 g/mol
Finally, we shall determine the concentration of the acid in gdm¯³. This can be obtained as follow:
Concentration (moldm¯³) = 0.0625 moldm¯³
Molar mass of H₂SO₄ = 98 g/mol
Concentration (gdm¯³) =?
Conc. (moldm¯³) = conc. (gdm¯³) / Molar mass
0.0625 = Conc. (gdm¯³) / 98
Cross multiply
Conc. (gdm¯³) = 0.0625 × 98
Conc. (gdm¯³) = 6.125 gdm¯³
Thus, the concentration of the acid in gdm¯³ is 6.125 gdm¯³
Which statement describes the movement of the medium by a transverse wave?
A. at an obtuse angle to the wave
B. parallel to the wave
C. at a right angle to the wave
D. at an acute angle to the wave
Answer:
A
Explanation:
But I'm not sure just my instinct
The statement that described the movement of the medium via the transverse wave should be that it should be parallel to the wave.
What is a transverse wave?It is the waves in which the motion considered all the points that should be on the wave oscillate along the paths at the right angles with respect to the wave of the direction. An example of this kind of wave should be electromagnetic, etc. Here, the movement should be parallel to the wave.
Hence, the correct option is b.
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g When water and perchloric acid (HClO4) are mixed, heat is released. The resulting solution is not an ideal solution, in terms of Raoult’s Law. How should the boiling point and the vapor pressure of a solution of HClO4 in H2O differ from what is expected for an ideal solution? A) boiling point higher than expected, vapor pressure lower than expected B) boiling point higher than expected, vapor pressure higher than expected C) boiling point lower than expected, vapor pressure lower than expected D) boiling point lower than expected, vapor pressure higher than expected E) boiling point and vapor pressure are both the same as expected for an ideal solution
Answer:
A) boiling point higher than expected vapor pressure lower than expected.
Explanation:
When water is introduced with heat it vaporize at a temperature of 100 degree centigrade. When hydrochloric acid is added to the water its boiling point of water increases slightly. The difference in the boiling point is due to the presence of heavier molecules in acid.
What would be the structural formula for sodium fluoride? (NaF)
Answer:
Formula and structure: The chemical formula of sodium fluoride is NaF and its molar mass is 41.99 g/mol. It is a simple ionic compound, made of the sodium (Na +) cation and fluoride (F -) anion. The solid salt exists as cubic crystals similar to the crystal structure of sodium chloride (NaCl).
Explanation:
Can you locate any mountains in the tropical zones?
Answer:
At even lower levels mountain lands grade into other types of landform and vegetation—e.g., tropical or temperate forest, savanna, scrubland, desert, or tundra. The largest and highest area of mountain lands occurs in the Himalaya -Tibet region; the longest nearly continuous mountain range is that along the west coast of the Americas from Alaska in the north to Chile in the south.
eh-
Explanation:
Which is an acceptable Lewis structure for a diatomic nitrogen molecule?
OA NEN
OB.
N
N
O C.
:N
N:
OD.
NEN
OENEN
Answer:
:N:::N:
Explanation: 10 valence electrons betwwen the 2
need an octet
and N needs 5 for a neutral formal charge
An acceptable Lewis structure for a diatomic nitrogen molecule is
:N:::N: .Option C is correct. This is further explained below.
What is Lewis structure for a diatomic nitrogen molecule?Lewis structure for a diatomic nitrogen molecule simply refers to the triple bond exists between two nitrogen atoms in the N2 Lewis structure.
In conclusion, The nitrogen molecule is diatomic, which means it is made up of two atoms of the same element.
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which one is the correct ans.
Answer:
Aluminium Sulphate
Explanation:
Aluminium sulphate is the most widely used aluminium coagulant. It is soluble in water and used as a coagulating agent in purification of drinking water and in waste water treatment plants.
Answer:
where are you from .. ...
one reaction that produces hydrogen gas can be represented by the unbalanced chemical equation Mg(s)+HCI(aq) -> MgCI(aq)+H2(g). What is the mass of HCI is consumed by the reaction of 3.25 mol of magnesium?
128 g HCl
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableStoichiometry
Reaction Mole RatiosUsing Dimensional AnalysisExplanation:Step 1: Define
[RxN - Unbalanced] Mg (s) + HCl (aq) → MgCl (aq) + H₂ (g)
↓
[RxN - Balanced] 2Mg (s) + 2HCl (aq) → 2MgCl (aq) + H₂ (g)
[Given] 3.25 mol Mg
[Solve] x g HCl
Step 2: Identify Conversions
[RxN] 2 mol Mg → 2 mol HCl
[PT] Molar Mass of H - 1.01 g/mol
[PT] Molar Mass of Cl - 35.45 g/mol
Molar Mass of HCl - 1.01 + 35.45 = 36.46 g/mol
Step 3: Stoich
[S - DA] Set up: [tex]\displaystyle 3.25 \ mol \ Mg(\frac{2 \ mol \ HCl}{2 \ mol \ Mg})(\frac{36.46 \ g \ HCl}{1 \ mol \ HCl})[/tex][S - DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 127.61 \ g \ HCl[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
127.61 g HCl ≈ 128 g HCl
The image shown here is a good illustration of which law?
Answer:
The answer is A.Newton's First law
An allergy medicine is usually stored in a cabinet at room termperature where its molecules move around each other. By
mistake, an intern transferred energy into the medicine. After one hour, the intern found the medicine and noticed that it
was a liquid. How were the molecules moving when the intern found the medicine? Explain why the molecules were
moving this way after the intern transferred energy ito the medicine.
Answer:
hello, can you pleas egive me the answer? i have the same exact question. thank you!
Explanation:
Which of the following statements best goes with the Law of Conservation of Energy?
all energy conversions are 100% efficient
O all energy from the sun is transferred to organisms directly by the 10% rule
O all of the sun's energy is either transformed into kinetic energy, and eventually heat energy
O all matter cannot be created or destroyed
Answer:
all letter cannot be created or destroyed just transformed
In humans, normal color perception (N) dominates the expression of color blindness (n), and both of these genes are carried on the X chromosome (XN or Xn). A woman with normal color vision has a color-blind father. Her husband is also color-blind.
a. What is the genotype of the colorblind man? ____
b. What is the genotype of the woman? ______
c. What is the probability of her daughter to be colorblind? __________%
d. What is the probability of her sons to be colorblind? _________%
WHO CAN HELP ME
Answer:
a: Nn or XN
b: Nn or Xn
c: 75%
d: 50%
Explanation:
WRITE A 3-4 SENTENCE SUMMARY ABOUT ATOMS.
Answer:
An atom is the smallest unit of matter that retains all of the chemical properties of an element. Atoms combine to form molecules, which then interact to form solids, gases, or liquids. For example, water is composed of hydrogen and oxygen atoms that have combined to form water molecules.
Explanation:
Answer:
Atom is the smallest particle in the universe. An atom is made up of sub-atomic particles. They are the protons (positively charged particle), electrons (negatively charged particles) and neutrons neutrally charged particles). The lightest atom ever known is Hydrogen atom. An atom is electrically neutral. When a atom looses or gains and electrons it is called an ions.
According to the tow of conservation of matter, we know that the total number of atoms does not change in a chemical reaction and thus mas is conserved This
is part of a chemical reaction hydrogen plus orygon yobis water Can you complete this moder? Reorganize the reactants in order to complete the productie
of the reaction
Your answer:
Answer:
no sé de eso perdón necesito los puntos
what does the picture depict about ecology?
How can weak acids and weak bases cause pH stress to cells?
a. Weak bases will only cause pH stress at low pH.
b. If a cell has transporters that are not well regulated, weak acids or weak bases can accumulate inside the cells and cause stress.
c. Only weak acids can cause stress by diffusing across a membrane at low pH.
d. At certain pH levels, both weak acids or weak bases will be uncharged, and thus are small uncharged molecules that can diffuse across a membrane and cause pH stress inside the cell. e. Weak acids and weak bases do not cause stress.
Answer:
b
Explanation:
If a cell has transporters that are not well regulated, weak acids or weak bases can accumulate inside the cells and cause stress.
A mixture of gaseous reactants is put into a cylinder, where a chemical reaction tums them into gaseous products. The cylinder has a piston that moves in or out, as necessary, to keep a constant pressure on the mixture of 1 atm. The cylinder is also submerged in a large insulated water bath. 1 atm pressure piston cylinder The temperature of the water bath is monitored, and it is determined from this data that 300.1J of heat flows out of the system during the reaction. The position of the piston is also monitored, and it is determined from this data that the system does 316.kJ of work on the piston during the reaction water bath gases exothermic.
Required:
a. Is the reaction exothermic or endothermic?
b. Does the temperature of the water bath go up or down?
Answer:
The reaction is exothermic
The temperature of the water bath goes up
Explanation:
An exothermic reaction is one in which energy flows out of the reaction system.
In this case, the system is the reaction vessel while the surrounding is the water bath. We see in the question that 300.1J of heat flows out of the system during the reaction. This is heat lost to the surroundings showing that the reaction is exothermic.
As energy is lost to the surroundings, the temperature of the water bath rises accordingly.
The three temperate marine climates are?
Marine west coast, humid subtropical, and Mediterranean.
A 1 mL sample weighs 4 g, the density of the sample is
What is geberal formula for alkane?
Answer:
CnH2n+2
Explanation:
Alkane have double and two atoms of hydrogen than carbon atoms
Like C4H10
n = 4
CnH2n+2
C4H2×4+2
C4H10
A 508-g sample of sodium bicarbonate (NaHCO3) contains how many moles of sodium bicarbonate (NaHCO3)?
molar mass = (22.99) + (1.01) + (12.01) + 3(16.00)
molar mass = 84.01 g/mol
//
(508g)(1 mol/84.01 g) = 6.0
There are 6.0 moles of sodium bicarbonate
A 508-g sample of sodium bicarbonate (NaHCO3) contains 0.6 moles of sodium bicarbonate (NaHCO3)
What is mass?Mass is defined as a dimensionless quantity representing the amount of matter in a particle or object. The SI unit of mass is kg.
Mole is defined as a standard scientific unit for measuring large quantities of very small entities
Molar mass = 22.99 + 1.01 + 12.01 + 3x16.00
= 84.01 g/mole
Moles of NaHCO3
= 508 g x 1 mole / 84.01
= 6.0 moles
Thus, 508-g sample of sodium bicarbonate (NaHCO3) contains 0.6 moles of sodium bicarbonate (NaHCO3)
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Decide whether a chemical reaction happens in either of the following situations. If a reaction does happen, write the chemical equation for it. Be sure your chemical equation is balanced and has physical state symbols. situation chemical reaction.
A strip of solid magnesium metal is put into a beaker of 0.042M SnCl3 solution.
Answer: [tex]3Mg(s)+2SnCl_3(aq)\rightarrow 3MgCl_2(aq)+2Sn(s)[/tex]
Explanation:
Single replacement reaction is a chemical reaction in which more reactive element displaces the less reactive element from its salt solution.
A more reactive element is one which can easily lose or gain electrons as compared to the other element.
As Magnesium is more reactive than tin, it can easily displace tin from its salt solution [tex](SnCl_3)[/tex] and form magnesium chloride and tin in elemental form.
The balanced chemical equation is:
[tex]3Mg(s)+2SnCl_3(aq)\rightarrow 3MgCl_2(aq)+2Sn(s)[/tex]
What is the atomic weight of Mercury?
Answer:
Not sure if I'm correct, but I think it's 200.59 u
Answer:
The answer is 200.59 u
Explanation:
Mercury has a mass of 3.3 x 1023kilograms. This mass is contained in a volume of 14.6 billion cubic miles (60.8 billion cubic km). The mass and volume of Mercury is only about 0.055 times that of Earth
• as it sits on top of a building that is 50 meters tall.
• as it is half-way through a fall off a building that is 50 meters tall and travelling 19.8 meters per second.
• as it is just about to hit the ground from a fall off a building that is 50 meters tall and travelling 28 m/s
What is the potential energy of the ball as it is half-way through the fall (25 meters high)?
what is the purpose of sand bath in preparation of ethane
Answer:
The sand bath spreads the heat out so that the flask is heated evenly. This reduces the chance of the flask breaking and ensures that there are no hot spots in the reaction mixture which could lead to excessive charring,
Explanation:
If potassium reacts so dangerously with water, and people are mostly made of water, why can we eat bananas without blowing up?
Answer:
A banana, like most other lifeforms, is about 70% water, and all the potassium it contains already exists in the form of K+ ions dissolved in water. Which is why bananas do not explode in water, or spontaneously combust.
on analysis an ammonium salt of an alkanoic acid gave 60.5% C and 6.5% H if 0.309g of the salt yield 0.0313g of Nitrogen determine the empirical formula of the salt [ H = 1, C =12, N = 14, O= 16]
Answer: C7H9NO2
Explanation:
%N = 0.0313/0.309 x 100
= 10.1%
%0 = 100 — (60.5 + 6.5 + 10.1)
= 22.9
C; 60.5/12 H; 6.5/1 N; 10.1/14 O; 22.9/16
C; 5.04/0.72 H; 6.5/0.72 N; 0.72/0.72 O; 1.43/0.72
Empirical formula — C7H9NO2
When two substances combine to form a mixture, the properties of the substances change. True False
Answer:
Tell students that sometimes when two (or more) substances are mixed together, a change occurs and another substance (or substances) is created. This is called a chemical reaction. Gas may form, heat may be produced, and color may change. These types of changes indicate that a chemical reaction has occurred.