Answer:
K⁺ and HPO₄²⁻ ions are present in K₂HPO₄
Explanation:
K₂HPO₄ consist of anion and cation such as HPO₄²⁻ and K⁺. We can see that the charge on HPO₄²⁻ is negative 2. Thus inroder to balance the charge and to neutral the compound two potassium ions are attached because the charge on one atom of potassium is K⁺.
Properties of K₂HPO₄ :
It is salt of phosphoric acid.
Its density is 2.44 g/cm³.
It is odourless compound.
It is white powder and soluble in water.
It is used in fertilizer because it provide phosphorus which is beneficial for the growth of plants.
It is also used as a additive in food.
It is inorganic compound and also used as buffering agent.
Explain what happens to the particles in a substance during a physical change. plllzzzzz hurry!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
When a physical change occurs, the arrangement of particles within the substance may change, but the atoms in the molecules remain bonded together.
Explanation:
Srry didn't see this till now, hope u got it right :)
Why is the reaction of a strong acid and a strong base classified as a neutralization reaction?
a. Water and a salt are produced, leaving the pH of the solution at a very high value.
b. Only water is produced, and water has a pH of 7.0.
c. Water and a salt are produced, leaving the pH of the solution at a value of 7.0.
d. Water and a salt are produced, leaving the pH of the solution at a very low value.
Answer:
Answer choice C
Explanation:
Basicly for the Arrhenius and Bornsted-Lowery theories of acids & bases, acid-base reactions can be divided into 4 forms...
a. Strong Acid + Strong Base (HCl/NaOH) => pH = 7 at Eqv. Pt.
b. Weak Acid + Strong Base (HOAc/NaOH) => pH > 7 at Eqv. Pt.
c. Strong Acid + Weak Base (HCl & NH₄OH) => pH < 7 at Eqv. Pt.
d. Weak Acid + Weak Base (HOAc & NH₄OH) => pH ∝ Stronger Electrolyte
*HOAc = Acetic Acid
*NH₄OH = Ammonium Hydroxide
For each type reaction the pH at equivalence point depends upon the salt generated by the acid-base reaction. Ions of the salt, if they react with water, (hydrolysis) will shift the pH up or down depending upon which ion reacts. If there is no reaction by the salt ions then the pH will depend only upon autoionization of water which gives pH = 7. Typically Strong Acids + Strong Bases will give a pH = 7 at equivalence point because the ions of the salt will not undergo hydrolysis in water.
Example:
Strong Acid + Strong Base
HCl(aq) + NaOH(aq) => NaCl(aq) + H₂O(l)
NaCl(aq) => Na⁺(aq) + Cl⁻(aq)
Na⁺(aq) + H₂O(l) => No Rxn (theoretically NaOH, but NaOH is a strong base which prefers to remain 100% ionized in water).
Cl⁻(aq) + H₂O(l) => No Rxn (theoretically HCl, but HCl is a strong acid which prefers to remain 100% ionized in water).
Therefore, the net rxn is H⁺ + OH⁻ => H₂O & pH = 7.0
Weak Acid + Strong Base
HOAc(aq) + NaOH(aq) => NaOAc(aq) + H₂O(l)
NaOAc(aq) => Na⁺(aq) + OAc⁻(aq)
Na⁺(aq) + H₂O(l) => No Rxn
OAc⁻(aq) + H₂O(l) => HOAc(aq) + OH⁻(aq) => (Excess OH⁻ functions to increase pH>7 at eqv. pt.)
Strong Acid + Weak Base
HCl(aq) + NH₄OH(aq) => NH₄Cl(aq) + H₂O(l)
NH₄Cl(aq) => NH₄⁺(aq) + Cl⁻(aq)
Cl⁻(aq) + H₂O(l) => No Rxn
NH₄⁺(aq) + H₂O(l) => NH₄OH(aq) + H⁺(aq) => (Excess H⁺ functions to decrease pH < 7 at eqv. pt. )
which statement about the sun is true?
A.The sun is a red giant
B. The sun will become a red giant
C. The sun began as a red giant
D. The sun cannnot become a reg giant
Bisulfite ion
What’s its ion pleaseeee helpppp meee
Answer:
An ester of sulfuric acid in which only one sulfuric acid hydroxyl group has been esterified. The product of esterification of both sulfuric acid hydroxyl groups is a sulfate ester.
How many different flame colors were you able to detect? How many different elements must have been exposed to the flame to produce this number of colors?
Answer:
This question is incomplete
Explanation:
This question is incomplete, however, there are some basic things that be used to answer the completed question on your own. Flame test is a test that is used to identify metal ions in a compound. Although, not all metal ions produce a colour in a flame test.
In a flame test, a "clean wire loop" is dipped in an unknown solid/mixture of solids, the loop where the solids must have attached to is then placed in the tip of a blue flame (perhaps of a bunsen burner). A colour change/changes is then observed during the course of this process. Some popular metal ions and there colour in flame test are listed below
Lithium ion ⇒ red
Sodium ion ⇒ yellow
Potassium ion ⇒ lilac
Calcium ion ⇒ orange-red
Barium ion ⇒ pale-green
Copper ion ⇒ blue-green
rubidium ion ⇒ red-violet
Lead ion ⇒ gray white
The number of different colours observed will ultimately determine the number of elements exposed to the flame
In addition to specialized glassware and tools, there are several other considerations required for the setup of a distillation apparatus.
Before assembling a distillation apparatus, lubricate the ground glass joints of each piece of glassware using _______. This helps seal the connection between two components. Once two components are fit together, use ________ to make the connections secure. Stabilize the complete distillation setup using a _______.
Answer: Grease; Clamp; Ring stand.
Explanation:
Distillation is being used while separating liquids from the nonvolatile solids, or in instance whereby there is a different boiling point between two or more liquids.
Before assembling a distillation apparatus, lubricate the ground glass joints of each piece of glassware using grease. This will help in lubricating the glass joints so that it won't squeeze out while under pressure.
This helps seal the connection between two components. Once two components are fit together, use clamp to make the connections secure. Clamp is a fastening device which will help in holding the components together so that they won't be separated.
Stabilize the complete distillation setup using a ring stand. The ring stand will help in the provision of support to the glassware.
Calculate the mass percent of oxygen in KMnO4.
Answer: 40.496%
Hope this helps! (:
PLEASE HELP!!!
The boiling point of pure water is 100 degrees Celsius. A student performs an experiment , expecting the water to boil at this temperature. However, the water does not begin boiling until 105 degrees Celsius. What can you infer from this observation ?
Answer:
The water is impure
Explanation:
Impurities raises the boiling points and lowers the melting point
Which object has the least kinetic energy? A. a heavy bowling ball moving quickly B. a heavy bowling ball moving slowly C. a light ping-pong ball moving quickly D. a light ping-pong ball moving slowly
Answer:
B
Explanation:
Answer:
kisses
Explanation:
mwah
Mathematically combine the three given reactions so that they sum to give a balanced chemical equation describing the production of propane, C3H8(g), from its elements, C(s,graphite) and H2(g). Show your intermediate steps. For example, if you must reverse reaction (c), write the reverse in the appropriate format; if you multiply reaction (a) by 2, write the updated equation. Make sure to enter the overall balanced equation at the bottom.
a. C3H8(g)+ 5O2(g) → 3CO2(g) + 4H2O(l)
b. C(s)+ O2(g) → CO2(g)
c. H2(g)+ 1/2O2→ H2O(l)
Answer:
The answer is in the explanation.
Explanation:
The reaction you want to obtain is:
3C(s) + 4H₂(g) → C₃H₈(g)
The sum of 3(b) + 4(c):
3b. 3C(s) + 3O₂(g) → 3CO₂
4c. 4H₂(g) + 2O₂(g) → 4H₂O(l)
3C(s) + 4H₂(g) + 5O₂(g) → 3CO₂(g) + 4H₂O(l)
Now, this reaction -(a):
-a. 3CO₂(g) + 4H₂O(l) → C₃H₈(g) + 5O₂(g)
3C(s) + 4H₂(g) → C₃H₈(g)
Ms. Lewis is a chemist micing two solutions together. A chemical reaction takes place, and the solution becomes warm. Which statement best describes what has happened?
O Energy has been created in the form of thermal energy.
O Energy has been transformed from one form to another
More energy has been created than has been destroyed.
a The chemical energy of the solution has been destroyed.
Answer:
It would have to tp be "Energy is being transformed from one form to another".
Explanation:
The reason I know this is because energy can neither be created nor destroyed only transformed into new forms.
Answer:
Energy has been transferred from one form to another.
Explanation:
got it right
Which of the following is a form of potential energy?
Group of answer choices
Light energy
Sound energy
Elastic energy
Kinetic energy
Answer:
elastic potential energy which is also called spring energy.
a hammer has the volume of 11.5 cubic centimeters. it also has the mass of 500 grams. what is the hammer density
Answer:
The answer is 43.48 g/cm³Explanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question
mass = 500 g
volume = 11.5 cm³
We have
[tex]density = \frac{500}{11.5} \\ = 43.47826086...[/tex]
We have the final answer as
43.48 g/cm³Hope this helps you
Help and explain step by step if you can!
Answer:
the third one
Explanation:
if you look at it mathematically its the one that makes the most sense
Given the image below, which calculation will NOT give you the correct average atomic mas C-12 C-13 (0.6.12)+0.4.13) (60-12)+40-13) (12+12+12-12-12+12+13+13+13+13)/10 16/10) 12+(4/10) 13
Answer:
Correct Answer: B. (60⋅12)+(40⋅13)
Explanation:
WHAT IS THE MASS OF AN OBJECT WHOSE
DENSITY IS 0.23 G/ML AND A VOLUME OF
22.5 ML?
Answer:
The answer is 5.18 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volumeFrom the question
volume = 22.5 mL
density = 0.23 g/mL
We have
mass = 0.23 × 22.5 = 5.175
We have the final answer as
5.18 gHope this helps you
Determine the percentage of calcium in Ca3(PO3)2.
Answer:
[tex]\%Ca=38.76\%[/tex]
Explanation:
Hello.
In this case, since percent compositions are computed by knowing the number of atoms of the required atom, its atomic mass and the molar mass of the compound at which it is, thus, for calcium we have:
[tex]\%Ca=\frac{3*m_{Ca}}{M_{Ca_3(PO_4)_2}} *100\%[/tex]
Thus, since calcium weights 40.08 g/mol and calcium phosphate 310.2 g/mol, the by mass percent of calcium turns out:
[tex]\%Ca=\frac{3*40.08g/mol}{310.2g/mol} *100\%\\\\\%Ca=38.76\%[/tex]
Best regards!
caed for this question.
A student reads a barometer in the laboratory and finds the prevailing atmospheric pressure to be 731 mm Hg. Express this
pressure in atmospheres, kilopascals, torrs, pounds per square inch, and pascals.
Hint: 1 atm
101.3 kPa = 760 torr = 760 mm Hg = 14.69 psi = 1.013*10Pa
mm Hg
atm
kPa
torr
psi
Pa
731
Submit Answer
Retry Entire Group
8 more group attempts remaining
Answer:
0.962 atm.
97.4 kPa.
731 torr.
14.1 psi.
97,434.6 Pa.
Explanation:
Hello.
In this case, given the available factors equaling 1 atm of pressure, each required pressure turns out:
- Atmospheres: 1 atm = 760 mmHg:
[tex]p=731mmHg*\frac{1atm}{760mmHg} =0.962atm[/tex]
- Kilopascals:: 101.3 kPa = 760 mmHg:
[tex]p=731mmHg*\frac{101.3kPa}{760mmHg} =97.4kPa[/tex]
- Torrs: 760 torr = 760 mmHg:
[tex]p=731mmHg*\frac{760 torr}{760mmHg} =731 torr[/tex]
- Pounds per square inch: 14.69 psi = 760 mmHg:
[tex]p=731mmHg*\frac{14.69}{760mmHg} =14.1psi[/tex]
- Pascals: 101300 Pa = 760 mmHg:
[tex]p=731mmHg*\frac{101300Pa}{760mmHg} \\\\p=97,434.6Pa[/tex]
Best regards.
What is the change of an atom of one element (atom) to an atom of different element called?
The _______,
who loved knowledge and built schools to help their people learn, were
foundational in the study of science.
A.French
B.Chinese
C.Romans
D.Greeks
what formation is the result of wind erostion
Answer:
Wind erosion abrades surfaces and makes desert pavement, ventifacts, and desert varnish. Sand dunes are common wind deposits that come in different shapes, depending on winds and sand availability.
Use the conversion factor above to find the meters in 2.7 x 103 kilometers.
1km/1000m
Answer:
2.7 × 10⁶ m
Explanation:
Step 1: Given data
Length: 2.7 × 10³ kilometers
Step 2: Convert "2.7 × 10³ kilometers" to meters
To convert a length from kilometers to meters we need the conversion factor 1 km/1000 m. We will multiply the length by the inverse of this factor so that kilometers are canceled and the final unit is meter.
2.7 × 10³ km × (1000 m/1 km) = 2.7 × 10⁶ m
2.7 × 10³ kilometers is equal to 2.7 × 10⁶ meters.
At a certain temperature the rate of this reaction is first order in with a rate constant of : Suppose a vessel contains at a concentration of . Calculate the concentration of in the vessel seconds later. You may assume no other reaction is important. Round your answer to significant digits.
Complete question is;
Consider this reaction: 2 HI(g) ⇄ H₂(g) + I₂(g)
At a certain temperature, this reaction follows first - order kinetics with a rate constant of 0.684 s^(-1). Suppose a vessel contains HI at a concentration of 0.32 M. Calculate the concentration of HI in the vessel 0.88 seconds later.
You may assume no other reaction is important.
Round your answer to 2 significant digits
Answer:
0.18 M
Explanation:
We are given;
Initial concentration of HI = 0.32 M
Time = 0.88 s
Rate is given as 0.684 s^(-1)
Now, we want to find the concentration of HI in the vessel 0.88 seconds later. It can be gotten from the formula;
ln (HI) = ln (HI)₀ - (kt)
Where;
(HI)₀ is the initial concentration
k is the reaction rate constant
t is time
Plugging in the relevant values, we have;
ln (HI) = In (0.32) - (0.684 × 0.88)
ln (HI) = -1.1394 - 0.6019
ln (HI) = -1.7413
(HI) = e^(-1.7413)
(HI) = 0.175 M ≈ 0.18 M
Tell how many atoms of each element are in one molecule of the substance of table salt
Answer:
Explanation:
Then, multiply the number of moles of Na by the conversion factor 6.02214179×1023 atoms Na/ 1 mol Na, with 6.02214179×1023 atoms being the number of atoms in one mole of Na (Avogadro's constant), which then allows the cancelation of moles, leaving the number of atoms of Na.Aug 15, 2020
a mechanical pencil has the mass of 55.5 grams the volume of the pencil is 11.5 cubic centimeter what is the density of the pencil
Answer:
D = M/V
Explanation:
D = 55.5g/11.5cm^3
D = 4.83g/cm^3
1. If an atom of calcium has a mass of 40:
a. Protons =
b. Neutrons =
2. If an atom of krypton has a mass of 84:
a. Protons =
b. Neutrons =
3. If an atom of tin haſ a mass of 119:
a. Protons =
b. Neutrons =
4. If an atom of tungsten has a mass of 184:
a. Protons
b. Neutrons =
Answer:
1. If an atom of calcium has a mass of 40:
a. Protons = 20
b. Neutrons = 20
2. If an atom of krypton has a mass of 84:
a. Protons = 36
b. Neutrons = 48
3. If an atom of tin has a mass of 119:
a. Protons = 50
b. Neutrons = 69
4. If an atom of tungsten has a mass of 184:
a. Protons = 74
b. Neutrons =110
2. A shopper in a supermarket takes a box of sugar from a shelf that is 1.5 m high because he is
going to bake some muffins. He also needs to get some blueberries. The sugar has a weight of 5N.
What Potential Energy did the sugar have before it was taken from the shelf?
Explanation:
kinetic energy?? idek hope I helped in anyway possible
Answer:
7.5 joules also 7.5 J
Explanation:
Identify the term that applies to each definition.
A. A sample prepared using the solvent and any other chemicals in the sample solutions, but not the absorbing substance
B. A square-shaped container, typically made of quartz, designed to hold samples in a spectrophotometer
C. A measurement of the amount of light that passes through a sample
D. A measurement of the amount of light taken in by a sample
E. A unit commonly used in spectrophotometry that is inversely proportional to energy and commonly measured in nanometers
Answer:
A. Reference blank
B. Cuvettes
C. Transmittance
D. Absorbance
E. Wavelength
Explanation:
A reference blank is a sample prepared using the solvent and any other chemicals in the sample solutions, but not the absorbing substance.
A square-shaped container, typically made of quartz, designed to hold samples in a spectrophotometer is known as Cuvettes.
A measurement of the amount of light that passes through a sample or percentage of light transmitted by the sample, with the respective intensities of the incident and transmitted beams is called Transmittance.
The measurement of the amount of light taken in by a sample is known as Absorbance
The wavelength is also the distance travelled by the wave during a period of oscillation. In spectrophotometry, the unit is inversely proportional to energy and commonly measured in nanometers
The sample that is prepared using the solvent and any other chemicals in the sample solutions, but not the absorbing substance is a reference blank.
A square-shaped container, typically made of quartz, designed to hold samples in a spectrophotometer is the cuvettes.
A measurement of the amount of light that passes through a sample is transmittance.
A measurement of the amount of light that is taken in by a sample is referred to as absorbance.
A unit that is commonly used in spectrophotometry that is inversely proportional to energy and commonly measured in nanometers is the wavelength.
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https://brainly.com/question/25220510
Octane C8H18 is an ingredient in gasoline. How many carbon atoms are in 20 kg of octane? help please
Answer:
Octane is a hydrocarbon and an alkane with the chemical formula C 8 H 18, and the condensed structural formula CH 3 (CH 2) 6 CH 3.Octane has many structural isomers that differ by the amount and location of branching in the carbon chain. One of these isomers, 2,2,4-trimethylpentane (commonly called iso-octane) is used as one of the standard values in the octane rating scale.
Chemical formula: C₈H₁₈
Molar mass: 114.232 g·mol−1
Melting point: −57.1 to −56.6 °C; −70.9 to −69.8 °F; 216.0 to 216.6 K
Solubility in water: 0.007 mg dm−3 (at 20 °C)
Answer:
Explanation:
Octane is C8H18, carbon is C. Therefore, for every mol of C8H18 there will be 8 mols of carbon.
Convert 20 kg of octane to mols octane using molar mass of octane.
Molar Mass octane = (8*12.011)+(18*1.008)=114.23 g/mol, where 8 and 18 are the atoms in the molecule and 12.011 and 1.008 are the respective molar masses of carbon and hydrogen.
20kg C8H18 *1000g/kg * mol C8H18/114.23g C8H18 = 175.1 mols octane.
Now convert that number of mols to mols carbon:
175.1 mol C8H18 * (8 mol C/mol C8H18)=1400.8 mol C.
Now remember that a mol of any given atom=6.022*10^23 atoms.
So 1400.8 mol C=1400.8*(6.022*10^23) atoms C, which is equal to your final answer, 8.4*10^26 atoms. (round to 2 significant digits since the initial number given, 20, has 2 significant digits.)
The main thing you want to look for here is your conversion factors. Once you have those down it is simple algebra from there, so be sure to practice those!
In x-ray studies of crystalline peptides, Linus Pauling and Robert Corey found that the C—N bond in the peptide link is intermediate in length (1.32 Å) between a typical C—N single bond (1.49 Å) and a C=N double bond (1.27 Å). They also found that the peptide bond is planar (all four atoms attached to the C—N group are located in the same plane) and that the two α-carbon atoms attached to the C—N are always trans to each other (on opposite sides of the peptide bond).
Required:
a. What does the length of the C—N bond in the peptide linkage indicate about its strength and its bond order (i.e., whether it is single, double, or triple)?
b. What do the observations of Pauling and Corey tell us about the ease of rotation about the C—N peptide bond?
Answer:
The C-N bond is a double bond.
There is no free rotation about the C-N bond
Explanation:
Linus Pauling and Robert Corey carried out a painstaking study of the bond lengths of peptide bonds as well as the stereo chemistry of atoms and groups around the peptide bonds in the crystal structures of molecules containing one or a few peptide bonds.
Their findings indicate that the bond length of the C-N bond in crystalline peptides is intermediate in length (1.32 Å) between a typical C—N single bond (1.49 Å) and a C=N double bond (1.27 Å). This is because the peptide bond has some double bond character as a result of resonance involving the C=O and -NH moieties of the amide.
As a result of resonance as shown above, the peptide bonds are found to be planar hence free rotation about the C-N bond is hindered. The peptide bond is mostly found in the trans configuration because it is more energetically favourable than the cis configuration.
Summarily, owing to the existence of a partial double bond character between the α carbon and the amine nitrogen in the peptide, there is no free rotation around the C-N bond.