Mrs. Wilson leaves her freshly-baked blueberry pie on the windowsill to cool. The delicious fragrance diffuses through the air with a diffusion coefficient of D = 0.2 cm2/s. How long does it take for Dennis to smell the pie in his treehouse 10 meters away? Give your answer in days, without entering the unit.

Answer:

too low

Explanation:

If our aim is to recover the naphthalene and measure its mass after separation, then we must not allow any vapour to escape.

Naphthalene is a sublime substance, it can be separated by sublimation. It changes directly from solid to gas. This vapour must be kept securely so that none of it escapes. If part of the naphthalene vapour happens to escape accidentally, then the measured mass of naphthalene will be too low compared to the mass of naphthalene originally present in the mixture.

Answer:

Coordinate or r = (7,9).

Explanation:

Data obtained from the question include the following:

Mid point = (8,7)

Coordinate of S = (9,5)

Coordinate of r =...?

We shall determine the coordinate of r as follow:

Let the coordinate of r be (x2, y2)

Mid point = (x1 + x2)/2 , (y1 + y2)/2

Mid point = (8,7)

Coordinate of S = (9,5)

x1 = 9

y1 = 5

x2 =?

y2 =?

The value of x2 can be obtained as follow:

8 = (x1 + x2)/2

8 = (9 + x2)/2

Cross multiply

9 + x2 = 2 × 8

9 + x2 = 16

Collect like terms

x2 = 16 – 9

x2 = 7

The value of y2 can be obtained as follow:

5 = (y1 + y2)/2

7 = (5 + y2)/2

Cross multiply

5 + y2 = 2 × 7

5 + y2 = 14

Collect like terms

y2 = 14 – 5

y2 = 9

Coordinate of r = (x2, y2)

Coordinate or r = (7,9)

Answer:

1.3 mL

Explanation:

First, get the density of the olive oil, which is 0.917 kg/mL. Then divide the mass by the density:

1.2kg/0.917kg/mL= 1.3086150491 mL. The kg cancel out, leaving us with mL.

It should have 2 significant figures, because 1.2kg has 2 and we are dividing.

The volume of olive oil will be nearly 1300mL or 1.30 L as per the given data.

Volume is a measurement of three-dimensional space that is occupied. It is frequently numerically quantified using SI derived units or various imperial units. The definition of length is linked to the definition of volume.

Volume is, at its most basic, a measure of space. The units liters (L) and milliliters (mL) are used to measure the volume of a liquid, also known as capacity.

This measurement is done with graduated cylinders, beakers, and Erlenmeyer flasks.

Here, it is given that mass of olive oil is 1.2kg.

We know that,

Density of olive oil = 0.917kg/l.

Volume = mass/density

Volume = 1.2/0.917.

Volume = 1.30 lit.

Volume = 1300mL.

Thus, the volume of olive oil will be 1300 mL.

For more details regarding volume, visit:

https://brainly.com/question/1578538

#SPJ2

Answer:

Al(NO₃)₃: Acidic.

C₂H₅NH₃NO₃: Acidic.

NaClO: Basic

RbI: pH-neutral

CH₃NH₃CN: Solution basic

Explanation:

The general rules to determine if a solution is acidic, basic or neutral are:

For the salts:

Al(NO₃)₃. The repective acid is HNO₃ (Strong acid) and the base is Al(OH)₃ (Weak base). As the salt comes from strong acid and weak base. SOLUTION ACIDIC

C₂H₅NH₃NO₃. The acid is HNO₃ (Strong acid) and the base C₂H₅NH₃OH (Weak base). SOLUTION ACIDIC.

NaClO. Tha acid is HClO (weak acid), and the base NaOH (Strong base). SOLUTION BASIC.

RbI: The acid is HI (Strong acid) and the base RbOH (Strong base). pH-NEUTRAL

CH₃NH₃CN. The acid is HCN (weak acid; pKb = 4.79) and  the base CH₃NH₃OH (weak base; pKa = 10.64). Both weak acid and base will produce each hydrolisis. The lower pK will predominate. That is the weak acid. SOLUTION BASIC

Solution of Al(NO₃)₃ and C₂H₅NH₃NO₃ salts is acidic, NaClO is basic and of RbI & CH₃NH₃cyanide is neutral in nature.

pH of any solution tells about the acidity or basicity of the solution, pH of any solution ranges from 0 to 14 and from acidity to basicity.

Hence, appropriate differentiation was done above.

To know more acidity or basicity, visit the below link:

https://brainly.com/question/172153

Answer:

37%

Explanation:

From the question, the equation goes does.

C2H6+ (1-x)+a(O2+3.76N2)=bC02 + cH2O + axO2 + 3.76dN2.

Mair=Mair/Rin

( MN)O2 + (MN)N2÷ (MN)O2 + (MN)N2 +(MN)C2H6.

33 . 3.25(1-x) + 28 × 13.16(1-x) ÷ 33 × 3.25(1-x) + 28 × 13.16(1-x). + 30.1

= 176/176+8

X= 0.37

0.37 × 100

X= 37%

Answer:

[tex]\rm Cl_2 + 2\; KBr \to Br_2 + 2\; KCl[/tex].

One chlorine molecule reacts with two formula units of (aqueous) potassium bromide to produce one bromine molecule and two formula units of (aqueous) potassium chloride.

Explanation:

Start by finding the formula for each of the compound.

Therefore, the ratio between [tex]\rm K[/tex] atoms and [tex]\rm Br[/tex] atoms in potassium bromide is supposed to be one-to-one. That corresponds to the empirical formula [tex]\rm KBr[/tex]. Similarly, the ratio between

The formula for chlorine gas is [tex]\rm Cl_2[/tex], while the formula for bromine gas is [tex]\rm Br_2[/tex].

Write down the equation using these chemical formulas.

[tex]\rm ?\; Cl_2 + ?\; KBr \to ?\;Br_2 + ?\; KCl[/tex].

Start by assuming that the coefficient of compound with the largest number of elements is one. In this particular equation, both [tex]\rm KBr[/tex] and [tex]\rm KCl[/tex] features two elements each.

Assume that the coefficient of [tex]\rm KCl[/tex] is one. Hence:

[tex]\rm ?\; Cl_2 + 1 \; KBr \to ?\;Br_2 + ?\; KCl[/tex].

Note that [tex]\rm KBr[/tex] is the only source of [tex]\rm K[/tex] and [tex]\rm Br[/tex] atoms among the reactants of this reaction.

There would thus be one [tex]\rm K[/tex] atom and one [tex]\rm Br[/tex] atom on the reactant side of the equation.

Because atoms are conserved in a chemical equation, there should be the same number of [tex]\rm K[/tex] and [tex]\rm Br[/tex] atoms on the product side of the equation.

In this reaction, [tex]\rm Br_2[/tex] is the only product with [tex]\rm Br[/tex] atoms.

One [tex]\rm Br[/tex] atom would correspond to [tex]0.5[/tex] units of [tex]\rm Br_2[/tex].

Similarly, in this reaction, [tex]\rm KCl[/tex] is the only product with [tex]\rm K[/tex] atoms.

One [tex]\rm K[/tex] atom would correspond to one formula unit of [tex]\rm KCl[/tex].

Hence:

[tex]\displaystyle \rm ?\; Cl_2 + 1 \; KBr \to \frac{1}{2}\;Br_2 + 1\; KCl[/tex].

Similarly, there should be exactly one [tex]\rm Cl[/tex] atom on either side of this equation. The coefficient of [tex]\rm Cl_2[/tex] should thus be [tex]0.5[/tex]. Hence:

[tex]\displaystyle \rm \frac{1}{2}\; Cl_2 + 1 \; KBr \to \frac{1}{2}\;Br_2 + 1\; KCl[/tex].

That does not meet the requirements, because two of these coefficients are not integers. Multiply all these coefficients by two (the least common multiple- LCM- of these two denominators) to obtain:

[tex]\displaystyle \rm 1\; Cl_2 + 2 \; KBr \to 1\;Br_2 + 2\; KCl[/tex].

Answer:

Pressure exerted by the gas is 574.85 torr

Explanation:

Atmospheric pressure = 751 torr

but 1 torr = 1 mmHg

therefore,

atmospheric pressure = 751 mmHg

1 mmHg = 133.3 Pa

therefore,

atmospheric pressure = 751 x 133.3 = 100108.3 Pa

distance labeled (tube section with mercury) = 176 mm

the pressure within the tube will be

[tex]P_{tube}[/tex] = ρgh

where ρ is the density of mercury = 13600 kg/m^3

h is the labeled distance = 176 mm = 0.176 m

g is acceleration due to gravity = 9.81 m/s^2

[tex]P_{tube}[/tex]  = 13600 x 9.81 x 0.176 = 23481.216 Pa

The general equation for the pressure in the manometer will be

[tex]P_{atm}[/tex] = [tex]P_{tube}[/tex] + [tex]P_{gas}[/tex]

where [tex]P_{atm}[/tex]  is the atmospheric pressure

[tex]P_{tube}[/tex]  is the pressure within the tube with mercury

[tex]P_{gas}[/tex] is the pressure of the gas

substituting, we have

100108.3 = 23481.216 + [tex]P_{gas}[/tex]

[tex]P_{gas}[/tex] = 100108.3 - 23481.216 = 76627.1 Pa

This pressure can be stated in mmHg as

76627.1 /133.3 = 574.85 mmHg

and also equal to 574.85 torr

Answer:

A

Explanation:

The number of protons indicates the element so we know it's potassium. To get the number of neutrons you subtract the number of protons (19) from the mass number which for potassium is 39.

39-19=20 neutrons

Because you have 18 neutrons then yours would be an isotope.

Answer: A. Isotope of potassium(K)

Explanation: Founders Educere answer.

The question is incomplete, the complete question is;

What is the purpose of reacting 2.0mL of HNO3 with 2.0 mL of H2SO4 in a separate test tube, prior to adding it to the solution containing the substrate? more than one answer is possible

A) The release of a water molecule that acts as an electrophile in the reaction with methyl benzoate.

B) The formation of nitronium ion, which acts an electrophile in the reaction with methylbenzoate.

C)The formation of bisulfate (hydrogen sulfate), which acts as an electrophile in the reaction with methylbenzoate.

D)The release of a water molecule that acts as a nucleophile in the reaction with methyl benzoate.

Answer:

B) The formation of nitronium ion, which acts an electrophile in the reaction with methylbenzoate.

Explanation:

The benzene ring is known to be stable hence it can only undergo a substitution reaction with the aromatic ring still intact. When the substitution reaction involves an electrophile we refer to the process as electrophillic aromatic substitution. Electrophilic aromatic substitution is a useful synthetic route for many organic compounds.

In the electrophilic substitution of methyl benzoate using the 1:1 volume ratio mixture of H2SO4/HNO3, the nitronium ion (NO2+) is the electrophile generated in the test tube. It is this NO2+ that now reacts with the methyl benzoate to yield the reaction product.

Answer:

Aromatic Hydrocarbons

Explanation:

Aromatic (Pleasant Odour) Hydrocarbons are those having pleasant odours.

Answer:

substituted hydrocarbons

Explanation:

i think

Answer:

[tex]pKa=3.70[/tex]

Explanation:

Hello,

In this case, given the information, we can compute the concentration of hydronium given the pH:

[tex]pH=-log([H^+])\\[/tex]

[tex][H^+]=10^{-pH}=10^{-2.18}=6.61x10^{-3}M[/tex]

Next, given the concentration of the acid and due to the fact it is monoprotic, its dissociation should be:

[tex]HA\rightleftharpoons H^++A^-[/tex]

We can write the law of mass action for equilibrium:

[tex]Ka=\frac{[H^+][A^-]}{[HA]}[/tex]

Thus, due to the stoichiometry, the concentration of hydronium and A⁻ are the same at equilibrium and the concentration of acid is:

[tex][HA]=0.2230M-6.61x10^{-3}M=0.2164M[/tex]

As the concentration of hydronium also equals the reaction extent ([tex]x[/tex]). Thereby, the acid dissociation constant turns out:

[tex]Ka=\frac{(6.61x10^{-3})^2}{0.2164}\\ \\Ka=2.02x10^{-4}[/tex]

And the pKa:

[tex]pKa=-log(Ka)=-log(2.02x10^{-4})\\\\pKa=3.70[/tex]

Regards.

Answer:

A

Explanation:

infer means use data to reach conclusion.

Answer:

(a) [tex]Ksp=4.50x10^{-7}[/tex]

(b) [tex]Ksp=1.55x10^{-6}[/tex]

(c) [tex]Ksp=2.27x10^{-12}[/tex]

(d) [tex]Ksp=1.05x10^{-22}[/tex]

Explanation:

Hello,

In this case, given the solubility of each salt, we can compute their molar solubilities by using the molar masses. Afterwards, by using the mole ratio between ions, we can compute the concentration of each dissolved and therefore the solubility product:

(a) [tex]BaSeO_4(s)\rightleftharpoons Ba^{2+}(aq)+SeO_4^{2-}(aq)[/tex]

[tex]Molar\ solubility=\frac{0.0188g}{100mL} *\frac{1mol}{280.3g}*\frac{1000mL}{1L}=6.7x10^{-4}\frac{mol}{L}[/tex]

In such a way, as barium and selenate ions are in 1:1 molar ratio, they have the same concentration, for which the solubility product turns out:

[tex]Ksp=[Ba^{2+}][SeO_4^{2-}]=(6.7x10^{-4}\frac{mol}{L} )^2\\\\Ksp=4.50x10^{-7}[/tex]

(B) [tex]Ba(BrO_3)_2(s)\rightleftharpoons Ba^{2+}(aq)+2BrO_3^{-}(aq)[/tex]

[tex]Molar\ solubility=\frac{0.30g}{100mL} *\frac{1mol}{411.15g}*\frac{1000mL}{1L}=7.30x10^{-3}\frac{mol}{L}[/tex]

In such a way, as barium and bromate ions are in 1:2 molar ratio, bromate ions have twice the concentration of barium ions, for which the solubility product turns out:

[tex]Ksp=[Ba^{2+}][BrO_3^-]^2=(7.30x10^{-3}\frac{mol}{L})(3.65x10^{-3}\frac{mol}{L})^2\\\\Ksp=1.55x10^{-6}[/tex]

(C) [tex]NH_4MgAsO_4(s)\rightleftharpoons NH_4^+(aq)+Mg^{2+}(aq)+AsO_4^{3-}(aq)[/tex]

[tex]Molar\ solubility=\frac{0.038g}{100mL} *\frac{1mol}{289.35g}*\frac{1000mL}{1L}=1.31x10^{-4}\frac{mol}{L}[/tex]

In such a way, as ammonium, magnesium and arsenate ions are in 1:1:1 molar ratio, they have the same concentrations, for which the solubility product turns out:

[tex]Ksp=[NH_4^+][Mg^{2+}][AsO_4^{3-}]^2=(1.31x10^{-4}\frac{mol}{L})^3\\\\Ksp=2.27x10^{-12}[/tex]

(D) [tex]La_2(MoOs)_3(s)\rightleftharpoons 2La^{3+}(aq)+3MoOs^{2-}(aq)[/tex]

[tex]Molar\ solubility=\frac{0.00179g}{100mL} *\frac{1mol}{1136.38g}*\frac{1000mL}{1L}=1.58x10^{-5}\frac{mol}{L}[/tex]

In such a way, as the involved ions are in 2:3 molar ratio, La ion is twice the molar solubility and MoOs ion is three times it, for which the solubility product turns out:

[tex]Ksp=[La^{3+}]^2[MoOs^{-2}]^3=(2*1.58x10^{-5}\frac{mol}{L})^2(3*1.58x10^{-5}\frac{mol}{L})^3\\\\Ksp=1.05x10^{-22}[/tex]

Best regards.

Answer:

The Nuclear magnetic resonance is the process this technique does not use radiation.

The  ms is an sensitive technology can be a massive number and small sample of the blood.

Explanation:

The Nuclear magnetic resonance we look at the both side of that coin.

The technique provides that fatty acid composition and various including amino acids.

These are contain the complementary these biomarkers, that are suitable for all kinds of studies. there are many types of research:-

(1) A powerful tool metabolic (2) A versatile tool research (3) Quick analysis (4) Low cost analysis.

The MS is an extremely sensitive technology using a very small number of the blood.

(1) Powerful techniques (2) Highly method (3) Large number of metabolites (4)Small sample volume

MS can be fine mapping metabolic pathways to sign analytical strategy.

Answer:

F

Explanation:

Halogens may interact with the benzene ring via inductive or resonance effects. Halogens deactivate the benzene ring by inductive effect rather than by resonance effects.

The lone pairs of electrons present on the halogen atoms may be donated to the ring by resonance, but an opposite effect, the inductive pull (-I inductive effect) of the halogen atoms on electrons away from the benzene ring due to the high electro negativity of the halogens leads to a deactivation of the ring towards electrophilic substitution.

Hence inductive electron withdrawal by the halogen atom predominates over electron donation by resonance effect and the benzene ring g is deactivated towards electrophilic substitution at the ortho and para positions.

Answer:

2.30 × 10⁻⁶ M

Explanation:

Step 1: Given data

Concentration of Mg²⁺ ([Mg²⁺]): 0.039 M

Solubility product constant of Mg(OH)₂ (Ksp): 2.06 × 10⁻¹³

Step 2: Write the reaction for the solution of Mg(OH)₂

Mg(OH)₂(s) ⇄ Mg²⁺(aq) + 2 OH⁻(aq)

Step 3: Calculate the minimum [OH⁻] required to trigger the precipitation of Mg²⁺ as Mg(OH)₂

We will use the following expression.

Ksp = 2.06 × 10⁻¹³ = [Mg²⁺] × [OH⁻]²

[OH⁻] = 2.30 × 10⁻⁶ M

Answer:

4.33 L

Explanation:

Step 1: Given data

Initial volume of the balloon (V₁): 3.00 L

Initial pressure of the balloon (P₁): 765 torr

Final  volume of the balloon (V₂): ?

Final pressure of the balloon (P₂): 530 torr

Step 2: Calculate the final volume of the balloon

If we consider Helium to behave as an ideal gas, we can calculate the final volume of the balloon using Boyle's law.

[tex]P_1 \times V_1 = P_2 \times V_2\\V_2 = \frac{P_1 \times V_1}{P_2} = \frac{765torr \times 3.00L}{530torr} = 4.33 L[/tex]

Answer:

Water

Explanation:

Solid potassium hydrogen tartrates (KHT) is soluble in water. This is especially at room temperature.

The solvent for KHT is water.

Answer:

Approximately 100 °C.

Explanation:

Hello,

In this case, since the entropy of vaporization is computed in terms of the heat of vaporization and the temperature as:

[tex]\Delta S_{vap}=\frac{\Delta H_{vap}}{T}[/tex]

We can solve for the temperature as follows:

[tex]T=\frac{\Delta H_{vap}}{\Delta S_{vap}}[/tex]

Thus, with the proper units, we obtain:

[tex]T=\frac{55500J/mol}{148J/(mol*K)} =375K\\\\T=102 \°C[/tex]

Hence, answer is approximately 100 °C.

Best regards.

Answer:

Do not conduct electricity as solids.

Explanation:

Hello,

In this case, we should remember that salts are formed when an acid and base react in order to yield the salt and water due to the ions exchange during neutralization chemical reactions. For instance, when hydrochloric acid  (acid) reacts with potassium hydroxide (base), sodium chloride (salt) and water are yielded via:

[tex]HCl+NaOH\rightarrow NaCl+H_2O[/tex]

Moreover, it is widely known that salts are formed by electrovalent/ionic bonds which involves electron transfer so the metallic atom becomes positively charged (cation) whereas the non-metallic atom becomes negatively charged (anion) once the electrons are received so it can conduct electricity when dissolved in water yet not when solid since electron transfer is facilitated by the aqueous media, otherwise, ions remain together. Thereby, answer is do not conduct electricity as solids.

Regards.

Answer:

c

Explanation:

Answer:

Explanation:

a ) Benzoic acid is formed . In any alkyl benzene derivative , potassium permanganate reacts to form carboxylic acid . It oxidises side chains to carboxylic acid .  

C₆H₅CH₃ + 0 = C₆H₅COOH + H₂O

O is provided by KMnO₄

b ) In this reaction isophthalic acid is formed .

C₆H₄(CH₃)₂ +O = C₆H₄(COOH)₂

c)

4-Propyl-3-t-butyltoluene

In this oxidation , three side chains of ring  are 1 ) 1-methyl 2 ) 3- butyl 3 ) 4 propyl .

The methyl and 4 - propyl groups are oxidised to di- carboxylic acid and 3 butyl group remains intact ( unoxidised )

Explanation:

first find the the number of moles of of zinc .

as the number of moles of zinc and ZnCl2 is same we can calculate the mass of ZnCl2.

Answer:

Molarity of the sulfuric acid solution is 4.61M

Explanation:

The neutralization of a base of OH⁻ with sulfuric acid, H₂SO₄, occurs as follows:

2 OH⁻ + H₂SO₄ → 2H₂O + SO₄²⁻

That means, 2 moles of base react with 1 mole of sulfuric acid.

If you add 0.400 moles of OH⁻, moles of sulfuric acid you need to neutralize this amount of OH⁻ are:

0.400 moles OH⁻ ₓ (1 mole H₂SO₄ / 2 moles OH⁻) = 0.200 moles of H₂SO₄

As you add 43.4mL = 0.0434L of sulfuric acid to neutralize this solution, molarity (Ratio between moles and liters) is:

0.200 moles H₂SO₄ / 0.0434L = 4.61M

Answer:

a

Explanation:

its made up of carbon and hydrogen

Radiologists are medical doctors that treat injuries using medical imaging (radiology)

Answer:

a person who uses X-rays or other high-energy radiation, especially a doctor specializing in radiology.

Explanation:

Answer:

104 48 Cd + 0 -1 e ---------> 104 47 Ag

Explanation:

In the process of electron capture, the nucleus captures an electron and thus converts a proton into a neutron with the emission of a neutrino. This process increases the Neutron/Proton ratio, the captured electron is usually from the K shell. An electron from a higher energy level now drops down to fill the vacancy in the K shell and characteristic X-ray is emitted. This process usually occurs where the Neutron/proton ratio is very low and the nucleus has insufficient energy to undergo positron emission.

For 104 48 Cd, the balanced equation for K electron capture is;

104 48 Cd + 0 -1 e ---------> 104 47 Ag

Answer:

C. 100

Explanation:

Biochemical researches and studies have found out that an average health hotdog has a calorie of between 100 and 150 which is usually dependent on the additives.

Since the nutrition label on the back of a package of hotdogs (purchased within the US) indicates that one hotdog contains 100 calories then it truly contains such amount of calories. The standard number of calories present in a hotdog is independent of the amount eaten by individuals.

Answer:

Strontium is smaller

Strontium has the higher ionization energy

Strontium has more valence electrons

Explanation:

It must be understood that both elements belong to the same period i.e the same horizontal band of the periodic table

While Rubidium is an alkali metal(group 1) while Strontium is an alkali earth metal(group 2)

Since they are in the same period, periodic trends would be useful in evaluating their properties

In terms of atomic radius, rubidium is larger meaning it has a bigger atomic size

Generally, across the periodic table, atomic radius is expected to decrease and thus Rubidium which is leftmost is expected to have the higher atomic radius

Since strontium belongs to group 2 of the periodic table, it has 2 valence electrons which is more than the single valence electron that rubidium which is in group 1 has

In terms of ionization energy, the atom with the higher number of valence electrons will have the higher ionization energy which is strontium in this case

Answer:

Isomers are molecules that have the same molecular method, however have a unique association of the atoms in space. That excludes any extraordinary preparations which can be sincerely because of the molecule rotating as an entire, or rotating about precise bonds.