Answer:
The open system evaporates the solvent in the solution
Explanation:
An open system is a system in which exchange of materials and energy can occur. If a TLC set up is left open, then the set up constitutes an open system.
During TLC, the sample is dotted on the plate and inserted into a suitable solvent. The solvent moves up the plate and achieves the required separation of the mixture.
Most of these solvents used used TLC are volatile organic compounds. Therefore, if the TLC set up is left open, the solvent will evaporate leading to poor results after running the TLC experiment.
Ion R2+ có phân lớp ngoài cùng là 3p6
a.Viết cấu hình electron của R và R2+ dưới dạng chữ và ô obitan.
b.Xác định Z, chu kỳ, nhóm, phân nhóm và tên nguyên tố R.
c.Viết công thức oxit cao nhất của R
d.Nêu bộ trị số có thể có của 4 số lượng tử đối với R
What is the pH of a solution with a 7.8 × 10−13 M hydronium ion concentration?
A) 1.9
B) 2.8
C) 11
D) 12
Answer:
12Explanation:
The pH of a solution can be found by using the formula
[tex]pH = - log [ { H_3O}^{+}][/tex]
From the question we have
[tex]ph = - log(7.8 \times {10}^{ - 13} ) \\ = 12.1079...[/tex]
We have the final answer as
12Hope this helps you
The pH of this solution with a 7.8 × 10⁻¹³ M concentration of hydronium ion is equal to: D. 12.
Given the following data:
Concentration of hydronium ion = 7.8 × 10⁻¹³ M.
What is pH?pH is literally the power of hydrogen ions and it can be defined as a measure of the molar concentration of hydrogen ions in a given solution.
How to calculate the pH of a solution?We would determine the pH of this solution by using this formula;
pH = -log[H⁺]
pH = -log(7.8 × 10⁻¹³).
pH = -(-12.1)
pH = 12.1 ≈ 12.
Read more on pH here: brainly.com/question/24233266
#SJP2
When aqueous solutions of potassium cyanide and hydrobromic acid are mixed, an aqueous solution of potassium bromide and hydrocyanic acid results. Write the net ionic equation for the reaction.
Answer:
hey there
Explanation:
CN- (aq) + H+ (aq) → HCN(I)
The reactants are aqueous solutions:
NaCN(aq) and HBr(aq)
When you mix these compounds you make pure HCN (I)
The molecular equation is:
NaCN(aq) + HBr(aq) → NaBr(aq) + HCN(I)
When you dissociate the reactants, you have: Nat(aq) +CN¯(aq) + H*(aq) + Br−(aq) → Nat(aq) + ->
Br (aq) + HCN(I)
Sodium bromide, it is a salt, that can also be
dissociated in the solution
To make, the net ionic equation you remove the repeated ions
CN- (aq) + H+ (aq) → HCN(I)
If you like my answer please mark as brainliest
cho 6,72 gam Fe tan hết trong dung dịch H2SO4 đặc nóng dư thu được V lít khí SO2. Giá trị của V là
4,032
BT electron
nSO2= 3nFe/
Determine whether each melting point observation corresponds to a pure sample of a single compound or to an impure sample with multiple compounds.
a. Wide melting point range __________
b. Experimental melting point is close to literature value _________
c. Experimental melting point is below literature value _________
d. Narrow melting point range __________
Answer:
Wide melting point range - impure sample with multiple compounds
Experimental melting point is close to literature value - pure sample of a single compound
Experimental melting point is below literature value - impure sample with multiple compounds
Narrow melting point range - pure sample of a single compound
Explanation:
The melting point of substances are easily obtainable from literature such as the CRC Handbook of Physics and Chemistry.
A single pure substance is always observed to melt within a narrow temperature range. This melting temperature is always very close to the melting point recorded in literature for the pure compound.
However, an impure sample with multiple compounds will melt over a wide temperature range. We also have to recall that impurities lower the melting point of a pure substance. Hence, the experimental melting point of an impure sample with multiple compounds is always below the literature value.
Calculate the energy in kj/mol of photon in red light of wavelength 656nm
Answer:
you don't know the answer?ha me too
How do we fix climate change?
The biggest problem of course is conspiracy theorys. Some say it is just a hoxe when really their chidrin or grandchidrin will sufer greatly from it. How do we educate ourselfs better?
Answer:
Hi so your answer is that to helping fix the climate change you have to : speak up , power your home with renewable engery , reduce water waste , dont waste food , and finally invest energy .
Explanation:
Really hope i helped , have a nice day :)
Answer:
we can reduce air pollution,which is one of the main cause of climate change.Climate change is not a hoxe if it is not attending the upcoming generations will suffer greatly.
Which one of the following statements concerning vitamin B12 is correct?
A\ it is present in plant products.
B\ its deficiency is most often caused by a lack of the vitamin in the diet.
C\ it requires a specific glycoprotein for its absorption.
D\ it is involved in the transfer of amino groups.
E\ the cofactor from is vitamin B12 itself.
Answer:
C it requires a specific glycoprotein for its absorption.
Out of the following statements concerning vitamin B12 the only statement which is correct- it requires a specific glycoprotein for its absorption.
Let's study some facts about vitamin B12:
Vitamin B12 is an essential vitamin found in foods such as meat, fish, and dairy. It requires a specific glycoprotein for its absorption. The body absorbs vitamin B12 from food in a two-step process.⇒First, hydrochloric acid in the stomach separates vitamin B12 from the protein that it's attached to.
⇒Second, the freed vitamin B12 then combines with a protein made by the stomach, called intrinsic factor, and the body absorbs them together.
Deficiency of Vitamin B12 leads to weakness and fatigue.Transport of B12 in extracellular fluids is dependent on three homologous carrier proteins:⇒intrinsic factor, transcobalamin (also known as transcobalamin II), and haptocorrin (also known as the R-protein or transcobalamin I).
Learn more:
brainly.com/question/9587963
A student measures her computer keyboard with a meter stick and finds that it has a width of 47.35 cm. Which statement about this measurement is true?
PLZZZZ HELP
A.) All the numbers are certain
B.) The 4 is uncertain
C.) The 5 is somewhat uncertain
D.) The 5 is certain
Which diagram shows the correct direction of electron flow in an electrolytic cell?
1)
2)
3)
4)
Sorry I couldn't put the diagram in, Thanks.
Answer:
A
Explanation:
What are the TWO characteristics of an effective collision?
Answer:
the TWO characteristics of an effective collision are:
1.Molecules collide with sufficient energy
2.Molecules collide with the proper orientation.
A solution is formed by dissolving 83.2 grams of copper II chloride (CuCl2) in 2.5 liters of water. The molar mass of CuCl2 is 134.45 g/mol.
What is the molarity of the solution?
Explanation:
the answer is in the above image
the total pressure in a mixture of gases is equal to the partial pressures of
Answer:
"The total pressure in a mixture of gases is equal to the sum of partial pressures of each gas"
Explanation:
Dalton's law of partial pressures state that, in a mixture of gases, the total pressure is equal to the sum of the partial pressure exerted by each gas of the mixture. The equation is:
Total pressure = Partial pressure Gas 1 + Partial pressure Gas 2 + .... + Partial pressure Gas n
To complete the sentence we can say:
"The total pressure in a mixture of gases is equal to the sum of partial pressures of each gas"
Considering the Dalton's partial pressure, the total pressure in a mixture of gases is equal to the sum of partial pressures of each gas.
The pressure exerted by a particular gas in a mixture is known as its partial pressure. So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:
[tex]P_{T} =P_{A} +P_{B}[/tex]
This relationship is due to the assumption that there are no attractive forces between the gases.
Dalton's partial pressure law can also be expressed in terms of the mole fraction of the gas in the mixture. The mole fraction is a dimensionless quantity that expresses the ratio of the number of moles of a component to the number of moles of all the components present.
So in a mixture of two or more gases, the partial pressure of gas A can be expressed as:
[tex]P_{A} =x_{A} P_{T}[/tex]
In summary, the total pressure in a mixture of gases is equal to the sum of partial pressures of each gas.
Learn more:
https://brainly.com/question/14239096?referrer=searchResultshttps://brainly.com/question/25181467?referrer=searchResultshttps://brainly.com/question/14119417What are the main modifications of John Dalton's atomic theory
Identify which of the compounds below are amphoteric.
a. hydrogen sulfide ion
b. sulfuric acid
c. dihydrogen phosphate
d. water
e. carbonate ion
Hydrogen sulfide ions, dihydrogen phosphate, and water are amphoteric. Therefore, option (a), (c), and (d) are correct.
What is amphoteric?Amphoteric can be stated as any compound that can be mixed with other compounds both as a base and an acid. Water is amphoteric as it can be transformed into a compound that can be mixed as an alkali or an acid.
Amphoterism is explaining the reactivity of a compound that indicates alkaline nature when mixed with an acid and describes acidic characteristics in an alkaline environment.
When acid reacts with water, it forms H₃O⁺ ion adding an H⁺ ion from the acid. When water is combined with a base, it donates a hydrogen H⁺ ion to the base and releases a hydroxide ion.
Besides water, there are many oxides and hydroxides are utilized in amphoterism. The substances that have both characteristics acids are proton donors and bases are proton acceptors are identified as amphoteric substances.
Therefore, HS⁻, H₂O, and H₂PO₄⁻ are amphoteric in nature.
Learn more about amphoteric, here:
https://brainly.com/question/2908795
#SPJ5
A certain shade of blue has a frequency of 7.16x10^14Hz. What is the energy of exactly one photon of this light? Planck’s constant h=6.626x10^-34 j•s.
Explanation:
the answer is in the image above
How many liters of hydrogen gas are required to react with 3.5" liters of oxygen gas in the following reaction? 2H2(g)+O2(g) -->2H2O(g)
Answer:
7 L of H₂.
Explanation:
The balanced equation for the reaction is given below:
2H₂ + O₂ —> 2H₂O
From the balanced equation above,
1 L of O₂ required 2 L of H₂.
Finally, we shall determine the volume of H₂ required to react with 3.5 L of O₂. This can be obtained as follow:
From the balanced equation above,
1 L of O₂ required 2 L of H₂.
Therefore, 3.5 L of O₂ will require
= 3.5 × 2 = 7 L of H₂.
Thus, 7 L of H₂ is required to for the reaction.
which is the correct orbital diagram for carbon
Answer:
Below
Explanation:
Got it right
Check the periodic table, then click electrons
Reaction or ionic equation for CuSO4(aq)+CaCO3(aq)
Answer:
CuCo3+CaSo4
Explanation:
when they react they form that compound in the reaction called double displacement.
What is the purpose of the scientific method?
Answer:
C. To remove any source of bias in an experience
Why can characteristics properties be used to identify unknown substances
Characteristic properties are used because the sample size and the shape of the substance does not matter.
10. What is the mass of SO3 when -8753 kJ of energy are used according
to the following equation?2S + 302 - 2003 AH = -791.4kJ Is this
Endothermic or Exothermic -8735kJ x mols03/kJ x gSO3/
molSO3
Answer:
Exothermic
1771 g
Explanation:
Step 1: Write the balanced thermochemical equation
2 S(s) + 3 O₂(g) ⇒ 2 SO₃(g) ΔH° = -791.4 kJ
Since ΔH° < 0, the reaction is exothermic.
Step 2: Calculate the moles of SO₃ produced when 8753 kJ of energy are released
According to the thermochemical equation, -791.4 kJ are released every 2 moles of SO₃ that are formed.
-8753 kJ × 2 mol/(-791.4 kJ) = 22.12 mol
Step 3: Calculate the mass corresponding to 22.12 moles of SO₃
The molar mass of SO₃ is 80.06 g/mol.
22.12 mol × 80.06 g/mol = 1771 g
How many aluminum atoms are in 2.88 g of aluminum?
Express your answer to three significant figures.
Answer:
Explanation:
1 Mole of Aluminum with mass 26.98g contains 6.02*10^23 atoms.
In 2.88g of Aluminum, there are 2.88/26.98*6.02*10^23 = 6.426*10^22 atoms.
Answer:
Explanation:
no of Al atoms = 2.88/26.98*6.02*10^23
= 6.426*10^22
= 6.43*10^22
Which of the following ions is formed when an acid is dissolved in a solution? (5 points) H+
O−
OH−
SO42+
Answer:
Hence, option B is correct. 1 and 2
Explanation:
NH 4 Cl is a weak base-strong acid salt.
NaCN is a salt of a strong base (NaOH) and weak acid (HCN).In water,
1. NH 4 Cl produces acidic solution
2. KHSO 4 produces acidic solution
because the neutral salt of strong base KOH and strong acid H 2 SO 4 is K 2 SO 4
3. NaCN produces basic solution
4. KNO
3 produces neutral solution
I think this is right but I hope its help ,ur welcome ♥️♥️
Answer:
H+
Explanation:
I took the test :)
Can someone help me answer this please
Answer:
A) 1.3 × 10⁻⁵ mol/L
Explanation:
Step 1: Write the balanced equation for the solution of AgCl
AgCl(s) ⇄ Ag⁺(aq) + Cl⁻(aq)
Step 2: Make an ICE Chart
AgCl(s) ⇄ Ag⁺(aq) + Cl⁻(aq)
I 0 0
C +S +S
E S S
If we replace the solubility (S) in the Ksp expression, we get,
Ksp = [Ag⁺] [Cl⁻] = S × S = S²
S = √Ksp = √1.8 × 10⁻¹⁰ = 1.3 × 10⁻⁵ mol/L
22)
)
Limestone can form as a result of
A)
metamorphosis of conglomerate rock
B)
cooling of molten rock under the oceans
C)
precipitation from evaporating water
D)
radioactive decay of dolostone
Answer:
tge answer is a
Explanation:
I'm smart like that
A student measured the maximum mass of salt that can dissolve in 100 mL of water at five different temperatures.
Which variable should go on the y-axis?
the volume of water
the temperature of water
the mass of salt
the mass of water
Answer:
the mass of salt
Explanation:
In an experiment, we have an independent variable and dependent variable. The independent variable is the variable that is manipulated to cause changes in other variable while the dependent variable is the variable that responds to the changes made to the independent variable and is measured.
In this case of experiment, the mass of the salt is the DEPENDENT VARIABLE while the different temperatures is the INDEPENDENT VARIABLE. In a graphical representation, the independent variable is always plotted on the x-axis or horizontal axis while the dependent variable is always plotted on the y-axis or vertical axis.
Since the dependent variable is the mass of the salt, it should be plotted on the y axis.
Answer:
The temperature of water
Explanation:
I took the test
Write a formula for the ionic compound that forms from magnesium
and oxygen.
Answer:
MgO
Explanation:
when nitric acid touches your skin a yellow spot develops what does the spot mean
Which of the following is a protein source of plant origin
Answer:
soy....plant protein also is found in vegtables and grain products.
The protein that is derived from the plant is soyabean. Protein-rich foods have a rich source of amino acids. Amino acids are required by the body for different cellular activities.
What are proteins?
Proteins are present in plant-based foods and animal-based foods. In nature, the plant-based foods that are rich in proteins are soybeans, beans etc. Animal products such as dairy products, milk, and cheese are rich sources of proteins.
Animal-based foods such as eggs, meat, and fish have a good amount of protein. The proteins are made up of amino acids. Peptide bonds connect each amino acid to the next.
Proteins are necessary for the body, as cells need amino acids for both structural and functional support. Not all cells of the body synthesise all amino acids. Some essential amino acids are required by the body and can be taken from external sources such as plants.
Hence, the plant-based protein is soyabean.
To learn more about the protein, here
https://brainly.com/question/17095120
#SPJ2.
The question is incomplete; the complete question may be the following:
1) Which of the following is a protein source of plant origin?
A)egg
B) Soyabean
C)cheese
D)Milk