The correct explanation for why there is no trend in atomic radii across a period for transition elements is:
As protons are added to the nuclei of the transition elements when moving from left to right across a period, electrons are added to the (−1)(n−1)d subshell. The number of electrons in the outermost shell (n) remain constant. This results in a roughly constant effective nuclear charge.
The key reason is that the number of electrons in the outermost shell remains constant. Therefore, as more protons are added to the nucleus, the effective nuclear charge experienced by the outermost electrons also remains roughly constant. This results in relatively similar atomic radii across the period.
The other options are incorrect:
Options 2 and 5: The effective nuclear charge decreases/increases, which is contrary to the constant charge in transition elements.
Options 3 and 4: The effective nuclear charge decreases/increases, which does not explain the constant radii. The charge should remain roughly constant.
So in summary, the constant number of outermost electrons and effective nuclear charge across a period explains the lack of any trend in atomic radii for transition elements.
The trend in atomic radii for main-group elements is not observed in transition elements because the electrons are added to the (−1)(n−1)d subshell instead of the outermost shell.
The trend in atomic radii for main-group elements is based on the number of electrons in the outermost energy level (n), which determines the size of the atom. However, in transition elements, the electrons are added to the (−1)(n−1)d subshell as protons are added to the nuclei when moving from left to right across a period.
This means that the number of electrons in the outermost shell (n) remains constant, resulting in a roughly constant effective nuclear charge and no significant change in atomic radii. Therefore, the trend in atomic radii for main-group elements is not observed in transition elements due to the unique electronic configurations and properties of the (−1)(n−1)d subshell.
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Calculate the Kc for the following reaction if an initial reaction mixture of 0.500 mole of CO and 1.500 mole of H2 in a 5.00 liter container forms an equilibrium mixture containing 0.198 mole of H2O and corresponding amounts of CO, H2, and CH4. CO (g) 3 H2 (g) rightwards harpoon over leftwards harpoon CH4 (g) H2O (g)
Answer:
can you be more clear with your question :
Use the portion of the periodic table shown below to answer the questions.
A portion of the first three columns of the periodic table is shown. Column one from top to bottom reads 11 sodium 22.990, 19 potassium 39.098, and 37 rubidium 85.468. Column two reads 12 magnesium 24.305, 20 calcium 40.078, and 38 strontium 87.62. Column three reads 21 scandium 44.956 and 39 yttrium 88.906.
Part 1: Name two elements that have the same properties as sodium (Na). (4 points)
Part 2: Determine the number of protons, electrons, and neutrons present in an atom of calcium (Ca). Explain how you determined your answer using complete sentences. (6 points)
The two elements that have the same properties as sodium are potassium and rubidium .
What is periodic table?The periodic table is an arrangement of the elements in order of increasing atomic number.
From the list, the two elements that have the same properties as sodium are potassium and rubidium .
Proton has an atomic number of 20 and a mass number of 40. The number of electrons is the same as the number of protons. Given that the atomic number is the number of protons present, we have 20 electrons and 20 protons.
Number of neutrons = Mass number - Number of protons
= 40 - 20 = 20 neutrons
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How does a conjugate acid differ from its conjugate base?
The conjugate acid is differ from its conjugate base as, conjugate acid is formed by strong base whereas conjugate base is formed by strong acid.
conjugate base is differ from conjugate acids by the presence of the proton. The conjugate acid is formed when proton is added to the bases whereas conjugate bases is formed when proton is released by the acids.
Example of corrugate acids are given below.
[tex]NH_{3}[/tex] → [tex]NH_{2} ^{-} +H^{+}[/tex]
In the above example [tex]NH_{2} ^{-}[/tex] is conjugate acids.
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The volume of a gas decreases to half of its original volume, but the gas maintains the same number of moles and temperature. According to the ideal gas law, what will most likely happen to the pressure?
It will double.
It will decrease.
It will increase slightly.
It will remain the same
A. when the volume of the gas is halved, the pressure of the gas will be doubled.
Pressure of the gas according to ideal gas lawPV = nRT
P = nRT/V
when the volume is halved
P= nRT/0.5V
P = 2nRT/V
P(new) = 2P(initial)
Thus, when the volume of the gas is halved, the pressure of the gas will be doubled.
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If an object has a temperature of 0 kelvin, how much energy is the object emitting? what is the wavelength of light emission according to wien's law?
This law (expressed mathematically as E = σT4) states that each gadget with temperatures above absolute zero (0K or -273°C or -459°F) emits radiation at a charge proportional to the fourth energy in their absolute temperature.
Wien's displacement law states that the black body radiation curve for one-of-a-kind temperatures height at a wavelength is inversely proportional to temperature.
Wien's displacement law It states that the better the temperature, the lower the wavelength λmax for which the radiation curve reaches its most. The shift to shorter wavelengths corresponds to photons of better energies. In other phrases, λmax (height wavelength) is inversely proportional to temperature.
Wien's regulation, named after the German Physicist Wilhelm Wien, tells us that gadgets of different temperatures emit spectra that height at distinctive wavelengths. hotter objects emit radiations of shorter wavelengths and for this reason, they seem blue.
Wien's regulation tells us that gadgets of various temperatures emit spectra that top at specific wavelengths. hotter gadgets emit a maximum of their radiation at shorter wavelengths; subsequently, they will seem like bluer. Cooler gadgets emit most of their radiation at longer wavelengths; consequently, they'll appear redder.
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Gas and dust are the primary components of the interstellar medium. They differ in structural form, elemental composition, and the density with which each is distributed across the interstellar medium. Complete the table by placing the physical descriptions of gas and dust in the appropriate column.
Gas: Structural Forms are Atoms and small molecules whereas Density is quite Low density
Dust: Structural Forms are Clumps of atoms and large molecules wherease Density is Extremely low density
Most of the gas between stars in our galaxy and other galaxies is hydrogen and helium, which is dispersed at different densities between the stars. The gas ratios are comparable to those of the Sun
A buildup of gas and dust falls under the influence of gravity to generate stars. From the moment the first gas cloud begins to compress to the time the star is formed and begins to shine like the Sun, the process of star creation takes roughly one million years.
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hich of the following is an oxidation-reduction reaction?
ZnS(s) + 2O2(g) Right arrow. ZnSO4(s)
CaO(s) + H2O(l) Right arrow. Ca(OH)2(s)
6Li2O(s) + P4O10(g) Right arrow. 4Li3PO4(s)
SO2(g) + H2O(l) Right arrow. H2SO3(aq)
The oxidation-reduction reaction from the reactions above is
ZnS(s) + 2O2(g) ------ ZnSO4(s)
What is redox reactions?Oxidation-reduction or redox reaction is the type of chemical reaction in which oxidation states of substrate changes
So therefore, the oxidation-reduction reaction from the reactions above is
ZnS(s) + 2O2(g) ------ ZnSO4(s)
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he expression below was formed by combining different gas laws.
V is proportional to StartFraction n T over P EndFraction.
Which law was used to determine the relationship between the volume and the number of moles in this equation?
Boyle’s law
Charles’s law
Avogadro’s law
Gay-Lussac’s law
C. The law that was used to determine the relationship between the volume and the number of moles is Avogadro’s law.
What is Avogadro’s law?Avogadro's law states that equal volumes of any gas contain the same number of molecules at the same temperature and pressure.
V ∝ n
where;
V is volume of the gasn is number of molesThus, the law that was used to determine the relationship between the volume and the number of moles is Avogadro’s law.
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Answer: C. Avogadro’s law
Explanation:
Uranium hexafluoride is a solid at room temperature, but it boils at 56C. Determine the density of uranium hexafluoride at 60.C and 745 torr.
Answer: The density of Uranium Hexafluoride at 60 °C and 745 torr is 0.0127 g/ml
Explanation:
Uranium Hexafluoride is only present as gas at 60 °C and 745 torr.
So, we know PV = nRT, from that
n/V = P/ RT = (745 torr)/(62.36 L-torr/mol*K)(337 K) = 0.0354 mol/L.
Density = (352.02 g/mol)(0.0354 mol/L)/(1000 cm³/L) = 0.0127 g/cm³
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What are you measuring when
you step on a scale?
A. the amount of Earth's gravity pulling you
down
B. the amount of atoms you contain
C. how high you can jump
D. your volume
Answer:
B. the amount of atoms you contain
Why is it difficult to see whether you have added the phenolphthalein to the flask solution before you have titrated it?
Whether in an alkali (pink) or an acid (colorless) solution, the phenolphthalein indicator has one of two distinct structures. Both structures are light-absorbing in the ultraviolet spectrum, which the human eye cannot see. So it is challenging.
What is phenolphthalein? The phthalein family of chemical compounds includes the indicator phenolphthalein (C20H14O4). The powder is a thin, crystalline yellowish-white to light orange powder. It has a pKa of 9.3, is barely soluble in water, and, when dissolved in alcohol, is used as an indicator for acid-base titration investigations.It is colorless in liquid form until pH 8.5 when it transforms from pink to dark red. Adolf von Baeyer, a German chemist, created phenolphthalein in 1871. He produced it by fusing phenol and phthalic anhydride in the presence of sulfuric acid (H2SO4) or zinc chloride. Phenolphthalein is closely linked to the triphenylmethane dyes (ZnCl2). The abbreviation "HIn" or "php" in shorthand notation is frequently used to refer to the chemical compound phenolphthalein, which has the formula C20H14O4. Its structure consists of 2 alcoholic groups, one ketone group, three hexagonal structures, and one pentagonal structure. Another compound with carbon, hydrogen, and oxygen chain structure is phenolphthalein.Phenolphthalein is frequently used as an indicator in acid-base titrations. Due to its water solubility, phenolphthalein is frequently dissolved in alcohols before use in experiments. It is a weak acid that can lose H+ ions in solutions. While the ion of phenolphthalein is purple, the phenolphthalein molecule is colorless.A common indicator used in titration experiments to show the titration's endpoint is phenolphthalein, an inert, colorless acid. Since this molecule dissociates to generate pink anions when dissolved in water, the endpoint is signaled by the production of pink color.To learn more about phenolphthalein, refer to:
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What is the best way to maintain control of the subsection when cutting with a vertical or diagonal cutting line
Palm to palm is referred to as the best way to maintain control of the subsection when cutting with a vertical or diagonal cutting line thereby preventing the risk of injuries or inaccuracy.
What is Palm to palm technique?This method is used during cutting or styling and involves the two palms of the hands in a position such that they are facing each other or opposite to one another and helps to reduce the different types of strain in the affected part of the body.
This method isn't a compulsory one to be done but is best suited for an individual who wants to maintain control of the subsection when cutting with a vertical or diagonal cutting line.
This is therefore the main reason why palm-to palm technique was chosen as the most appropriate choice.
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A gas diffuses 1/8 times faster than hydrogen gas. what is the molar mass of the gas?
129.02 g/mol
136.44 g/mol
140.81 g/mol
145.45 g/mol
Answer:
129.02 g/mol.
Explanation:
We apply grahams law of diffusion:
1/8 = √2.016/√m where m = molar mass
√m = 8√2.016
m = (8√2.016) = 129.02 g/mol.
Which describes the law of conservation of matter?
O A. Chemical reactions cannot happen.
B. Atoms cannot be created or destroyed in a reaction.
OC. Atoms are not involved in chemical reactions.
OD. Molecules cannot change into other molecules during a reaction.
SUBMIT
Answer:
answer is B
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A 25. 00 ml sample of acetic acid containing phenolphthalein indicator is titrated with 0. 1067 m naoh. The solution changes color after 30. 07 ml naoh has been added. What is the concentration of the acetic acid before titration?.
The concentration of acetic acid:
The concentration of the acetic acid before titration is 0.128 M
What is titration?
Titration is a quantitative analytical procedure that works by allowing a known analyte to gradually react with a titrant until an endpoint is reached.
Titration for weak acid and strong base:
Moles of acetic acid = moles of NaOH
Given:
Concentration of NaOH = 0.1067 M
Volume of NaOH = 30.07 ml = 0.03007 L
Calculation:
So, by using the formula, Concentration = Moles/Volume
Moles of NaOH = concentration x volume = 0.1067 x 0.03007 = 0.0032
Therefore, the moles of acetic acid = 0.0032 mole
Now, using the formula again for determining the concentration of acetic acid, we get,
Concentration = Moles/Volume
Concentration of acetic acid = 0.0032/0.025 = 0.128M
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If the symbol x represents a central atom, y represents outer atoms, and z represents lone pairs on the central atom, the structure the central x atom is single bonded to two y atoms, which are 180 degrees apart. The x atom has two lone pairs. Could be abbreviated as xy2z2. Classify each molecule according to its shape.
XY2Z - linear
XY2Z2 - bent(120)
XY2Z3 - bent(109)
XY3Z - trigonal pyramidal
XY3Z2 - t-shaped
XY4Z - see-saw
XY4Z2 - square planar
XY5Z - square pyramidal
Linear shape: A linear molecule is one that has its atoms arranged in a straight line.
Bent shape: One type of bent molecular geometry features a center atom with two lone pairs of electrons and two bond pairs attached to it. Other names for it include angular and V-shaped.
Trigonal pyramidal: A trigonal pyramid is a molecular shape that resembles a tetrahedron and has one atom at the top and three at the corners of the base.
T-Shaped: When a central atom has three ligands, the structure of the molecule is said to have a T-shaped molecular geometry.
See-saw: This shape is caused by a lone pair of electrons on the central atom.
Square planar: In square planar molecular geometry, constituent atoms create the square's four corners on the same plane and surround the center atom.
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A 5.2 molal aqueous solution of methyl alcohol, CH3OH, is supplied. What is the mole fraction of methyl alcohol in the solution?
Answer:
0.086
Explanation:
A 5.2 molal aqueous solution of methyl alcohol indicates that 5.2 moles of methyl alcohol are present in 1 kilogram (or 1000 g) of water. Water has a molecular weight of 18 g/mol.
(100g)/18g/mol=55.56 mol
5.2 mol/(5.2mol+55.56 mol)=0.086
Equation is balanced already
How many grams of propane are
needed to react completely with 48 grams of oxygen?
How many grams of carbon dioxide will be produced? (I-8 marks)
2 C4H10 13 O₂ = 8 CO2 +10 H₂O
Answer:
1.) 13 g C₄H₁₀
2.) 41 g CO₂
Explanation:
To find the mass of propane (C₄H₁₀) and carbon dioxide (CO₂), you need to (1) convert mass O₂ to moles O₂ (via molar mass), then (2) convert moles O₂ to moles C₄H₁₀/CO₂ (via mole-to-mole ratio from equation coefficients), and then (3) convert moles C₄H₁₀/CO₂ to mass C₄H₁₀/CO₂ (via molar mass). It is important to arrange the ratios in a way that allows for the cancellation of units. The final answers should have 2 sig figs to match the sig figs of the given value.
Molar Mass (C₄H₁₀): 4(12.011 g/mol) + 10(1.008 g/mol)
Molar Mass (C₄H₁₀): 58.124 g/mol
Molar Mass (CO₂): 12.011 g/mol + 2(15.998 g/mol)
Molar Mass (CO₂): 44.007 g/mol
Molar Mass (O₂): 2(15.998 g/mol)
Molar Mass (O₂): 31.996 g/mol
2 C₄H₁₀ + 13 O₂ ----> 8 CO₂ + 10 H₂O
48 g O₂ 1 mole 2 moles C₄H₁₀ 58.124 g
--------------- x ----------------- x -------------------------- x ------------------ =
31.996 g 13 moles O₂ 1 mole
= 13 g C₄H₁₀
48 g O₂ 1 mole 8 moles CO₂ 44.007 g
--------------- x ----------------- x -------------------------- x ------------------ =
31.996 g 13 moles O₂ 1 mole
= 41 g CO₂
If the rate law for a reaction A → P is rate = 3.37x10-3 M^-1 min-1 [A]^2 and the initial concentration of a is 0.122 M, calculate the half-life of A.
Rate = 3.37x10-3 M^-1 min-1 [A]^2 and the initial concentration of a is 0.122M.
A rate law indicates the rate of a chemical response depends on reactant concentration. For a response inclusive of the price regulation commonly has the form rate = ok[A]ⁿ, in which okay is a proportionality constant known as the fee regular and n is the order.
The charge of a chemical response is, perhaps, its maximum crucial asset because it dictates whether or not a reaction can arise all throughout an entire life. knowing the charge regulation, an expression concerning the price to the concentrations of reactants can assist a chemist to modify the response conditions to get an extra suitable rate.
half-life is the time taken for the radioactivity of a substance to fall to 1/2 its authentic cost whereas implies existence is the common life of all the nuclei of a particular risky atomic species.
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Which normal physiologic process contributes most to the need for acid-base balance?
C. Continuous metabolic production of free hydrogen ions
The processes of creating and breaking down glucose molecules are both examples of metabolic pathways. A metabolic pathway is a chain of related chemical reactions that feed each other. The pathway takes in a single or extra beginning molecule and, through a sequence of intermediates, converts them into merchandise.
Metabolism (stated: meh-TAB-uh-Liz-um) is the chemical reactions within the body's cells that alternate meals into power. Our bodies want this strength to do the entirety from moving to wondering to growing. particular proteins in the body manipulate the chemical reactions of metabolism.
A metabolic product is a compound produced via the cells and is excreted to the extracellular medium. it can be produced in the number one metabolism, e.g. carbon dioxide, ethanol, acetate, or lactate, or an extra complicated one, e.g. a secondary metabolite or a heterologous protein secreted to the extracellular medium.
The question is incomplete. Please read below to find the missing content.
Which normal physiologic process contributes most to the need for acid-base balance
A. Continuous organ production of bicarbonate from carbonic acid
B. Continuous alveolar exchange of oxygen and carbon dioxide
C. Continuous metabolic production of free hydrogen ions
D. Continuous kidney formation of urine from blood
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In each of the following substances nah, h2, and h2s, hydrogen is assigned an oxidation number of +1. is this correct? explain your reasoning
No It is not correct.
Correct oxidation number of hydrogen in NaH,H2 and H2S are:
Let x be the Oxidation state of ’H’ by oxidation state rule.x+1 =0 (Sodium has +1 Oxidation state )
x=−1
Therefore, -1 is oxidation number of Hydrogen in NaH.
The oxidation number of an element's atom in its standard state is zero. As a result, the oxidation number for H2 is zero.The hydrogen oxidation number in H2 is +1. As a result, that hydrogen atom can be reduced to lower oxidation states of hydrogen, such as 0 and -1. However, because +1 is the highest oxidation state of hydrogen, the hydrogen atom cannot be reduced any further.What is oxidation number?In simple terms, the oxidation number is the number assigned to elements in a chemical combination. The oxidation number is the number of electrons that atoms in a molecule can share, lose, or gain when forming chemical bonds with atoms of a different element.
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In a mass spectrometer, the ion with the highest abundance in the mass spectrum that is assigned a relative abundance of 100% is referred to as the
In a mass spectrometer, the ion with the highest abundance in the mass spectrum that is assigned a relative abundance of 100% is referred to as the base peak.
What does a mass spectrum base peak represent?The base peak is the greatest peak in the mass spectrum that corresponds to the most prevalent ion or the strongest peak in the spectrum. It could be the parent peak or a fragment ion peak, depending on the type of molecule. Sometimes the base peak may be the molecular ion peak.
What does a spectrophotometer's base peak mean?The base peak, which is the peak with the highest intensity in the spectrum, is given a value of 100 percent, and the intensities of the other peaks, including the molecular ion peak, are expressed as a percentage of the base peak (height x sensitivity factor). In addition to producing positive ions, bombarding a sample with electrons can also produce negative ions.
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An element with 11 neutrons, 11 protons, and 11 electrons would have a mass number o?
The mass number of element is 22.
The mass number is the sum of number of electrons/proton and number of neutron .
Mass number = number of proton/electron + number of neutrons
If an element with 11 neutrons, 11 protons, and 11 electrons then mass number is calculated as,
Mass number = number of proton/electron + number of neutrons
Mass number = 11 + 11 = 22
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A 1.00 L sample of HCl(aq) is prepared and has a pH of 1.045.
What mass of HCl(g) is dissolved?
The mass of HCl dissolved to form the solution is 3.285 g.
What is the mass of HCl dissolved?The mass of HCl is determined from the pH.
The concentration of hydrogen ions is given as:
[H⁺] = 10⁻1.045 = 0.09
1.0 moles of HCl is produced by 1.0 moles HCL
Moles of HCl = 0.09
Mass of HCl = 0.09 * 36.5
Mass of HCl = 3.285 g
In conclusion, the mass of HCl dissolved is obtained from the pH of the solution.
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Sometimes it is hard to find evidence at the scene of a suspicious fire because the act of putting out a fire is destructive.
True, sometimes it is hard to find evidence at the scene of a suspicious fire because the act of putting out a fire is destructive.
Firefighters must handle the area as a medical emergency incident in addition to a fire scene. The victim should be treated as evidence and kept in tact.Why is it difficult to find evidence of arson?
All unintentional causes of a fire-related incident must be eliminated before it can be deemed arson; this requires strong evidence that the fire was started intentionally. Arson is challenging to establish and later prosecute for this reason.Why is fire investigation difficult?
For three key reasons, arson investigations are challenging: The arsonist can prepare the fire in advance and bring all the necessary equipment with them. There is no requirement that the arsonist be present while the act is committed. Evidence linking the arsonist to the crime is destroyed by the fire itself.Learn more about fire investigation
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A cyclinder has a volume of 703 cm3 and a height of 18.5 cm. What can be concluded about the cyclinder
The volume of a cylinder's formula can be used to find the area of the base.
The formula - r2 h, where r is the cylinder's radius and h is its height, determines the volume of a cylinder.
The density of a cylinder is determined by its volume, which represents how much material may be immersed in it or carried inside of it. The formula r2h, where r is the radius of the circular base and h is the height of the cylinder, determines the volume of a cylinder. Any substance that can fill the cylinder consistently with liquid or another material may be used as the material.
The ratio of the base area to the height can be used to calculate the volume of a cylinder
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Which of the following explanations accounts for the fact that the ion-solvent interaction is greater for Li than for K
Li+ has a smaller ionic radius than K+
and smaller molecules have more collisions/interactions between each other
What is ion-solvent interaction ?In the case of ion-solvent interactions, the state in which the interac-tions exist is an obvious one; it is the situation in which ions are inside the solvent.
Ions are charged particles, and charges interact with other charges. So there will also be ion-ion, as well as ion-solvent, interactions in the solution.In the process of solvation, ions are surrounded by a concentric shell of solvent. Solvation is the process of reorganizing solvent and solute molecules into solvation complexes.Learn more about Ion-solvent interaction here:
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Why do we need to clamp the rubber tube when we are transferring the flask from the boiling water to the cool water
The flask assembly will heat up in hot water, pressure will build up inside the flask and it could explode.
The fingertip is kept in place throughout the transfer to prevent the seepage of the trapped air from the flask. Inside the tank, the flask is constantly upside down. The flask can be tipped at an angle to allow the air to escape.The entire contents of the pint will erupt out if only the bottom of the container is heated.Rubber stoppers are ideal for plugging joints or holes in laboratory glassware and creating a liquid-tight seal.What is the proper method for inserting glass tubing into a rubber stopper?
Lubricate the end of the glass tubing with a few drops of water, washing-up liquid, glycerol, or vegetable oil.Hold the glass tubing close to where it enters the hole in the rubber stopper.Ease the tubing into the hole with a gentle twisting motion.Learn more about rubber stopper
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22.PTCL wants to interlink 5 cities and the links should be between every two cities, how many links will be formed?
There will be 10 links for every two cities of the given 5 towns.
What is the formula for finding the number of combinations?The formula for the number of combinations is
[tex]\frac{n!}{r!(n-r)!}[/tex]
Where n is the number of objects and r is the number of choosing the objects.
How many pairs can be formed with the 5 cities and what are they?Consider the given 5 cities as A, B, C, D, and E
The pairs we can form:
(A, B), (A, C), (A, D), (A, E), (B, C), (B, D), (B, E), (C, D), (C, E), and (D, E)
How many links are formed?Since there are 10 pairs, there will be 10 links between those.
The number of combinations = [tex]\frac{n!}{r!(n-r)!}[/tex]
where n = 5 and r = 2
⇒ [tex]\frac{5!}{2!(5-2)!}[/tex]
⇒ 10
Therefore, there will be 10 links between those 5 cities.
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Silver bromide is the photosensitive material in 35 mm photographic film. When monochromatic light falls on film, the photons are recorded if
they contain sufficient energy to react with silver bromide in the film. The minimum energy needed to do this is approximately 57.9 kJ/mol. What
is the wavelength of this energy in nm?
The minimum energy needed by the photons to react with silver bromide in the film is approximately 57.9 kJ/mol. Then, the wavelength is 206 nm.
What is wavelength?Wavelength of a wave is the distance between two consecutive crests or troughs of the wave.
To find the wavelength of the energy in nm, we can use the equation:
E = hc/λ
where E is the energy in joules, h is Planck's constant (6.626 x 10⁻³⁴ J s), c is the speed of light (2.998 x 10⁸ m/s), and λ is the wavelength in meters.
First, we need to convert the energy from kJ/mol to J/photon:
57.9 kJ/mol = 57.9 x 1000 J/mol / 6.02 x 10²³ mol^-1
= 9.626 x 10²⁰ J/photon
Now we can use the equation above to find the wavelength:
9.626 x 10²⁰ J/photon = (6.626 x 10⁻³⁴ J s)(2.998 x 10⁸ m/s) / λ
Solving for λ, we get:
λ = hc/E = (6.626 x 10⁻³⁴ J s)(2.998 x 10^8 m/s) / 9.626 x 10⁻²⁰J/photon
= 2.06 x 10⁻⁷ m
Finally, we convert the wavelength from meters to nanometers:
λ = 2.06 x 10⁻⁷ m x (10⁻⁹ nm/m)
= 206 nm
Therefore, the wavelength of the energy needed to react with silver bromide in 35 mm photographic film is approximately 206 nm.
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