(1) Solution A and B are separated by a membrane that is permeable to Mg2 and impermeable to Cl-. Solution A contains 0.1 mM MgCl2, solution B contains 100 mM MgCl2. Mg2 will be at electrochemical equilibrium when solution A is around ____________ mV. 180 mV - 180 mV 90 mV - 90 mV 60 mV - 60 mV

Answer:

NaBH₄

Explanation:

First, we need to write the chemical formula of all the compounds:

Benzil: C₁₄H₁₀O₂

Sodium Borhydride: C₁₄H₁₀O₂

Hydrobenzoin: C₁₄H₁₄O₂

Now, let's write the reaction that is taking place and write all the products:

C₁₄H₁₀O₂ + 2NaBH₄ + 2H₂O -----------> C₁₄H₁₄O₂ + 2BH₃ + 2NaOH

We can see that the reaction is already balanced, so we don't need to do anything else.

The question of this exercise is to determine the limiting reagent of the reaction, in other words, the reagent that controls the reaction and produces the 2.22 g of the hydrobenzoin. And to know this we need to see the mole ratio in both reactants, and compare them to the given moles (That can be obtained with the given masses and MW)

According to the above reaction, we have a mole ratio of 1:2, so, let's calculate the moles of benzil and the borohydride, and see which of them is the limiting reactant:

moles C₁₄H₁₀O₂ = 2.56 / 210.23 = 0.0122 moles

moles NaBH₄ = 0.38 / 37.83 = 0.01 moles

moles  C₁₄H₁₄O₂ = 2.22 / 214.26 = 0.0103 moles

We have the moles of every species, now, let's see the mole ratio

If 1 mole of C₁₄H₁₀O₂ -----------> 2 moles of NaBH₄

Then 0.0122 moles C₁₄H₁₀O₂ ----------> X moles of NaBH₄

Solving for X:

X = 0.0122 * 2 / 1 = 0.0244 moles of NaBH₄ are required.

However, we only have 0.01 moles of NaBH₄, and we need so much more of this to completely react with the moles of the benzil. Therefore we can safely assume that the limiting reagent is the NaBH₄

Another data that we can use for this, is the fact the produced moles were 0.0103, and this value is nearest to the moles of NaBH₄ rather than the moles of the benzil.

Hope this helps

Given

Atomic symbol

Required

Atomic composition

Solution

Atomic number = number of protons = number of electrons

Mass Number (A) is the sum of protons and neutrons

Number of protons and Number of Neutrons  in nucleus

Number of electrons in the shell

From the picture:

protons = 3

neutrons = 4

electrons = 3

atomic number = protons = electrons = 3

mass number = protons + neutrons = 3+4 = 7

Answer: D

Explanation:

Cause If you head to the middle of the ocean and dive down, down, down to where the Earth's plates meet, you might find an undersea mountain split by a deep trench. It's called a mid-ocean ridge. Up through such trenches, brand-new molten rock is bubbling. That's the newest rock on Earth! How does the ocean floor make room for all that new rock? Simply by pushing the old rock aside. In fact, the ocean floor is actually spreading right at this minute, out away from the deep trenches where new rock is being formed. The oldest rock can be found farthest away from the trenches, right up near the continents. It's all part of a process called seafloor spreading. It's been going on for millions of years (at the rate of a few centimeters per year), but scientists are just now getting to know more about it. In fact, because evidence of seafloor spreading was first discovered in the 1940s and 50s, your great-grandparents may have never heard of it!

Answer:

6.576 g NaCl

Explanation:

2Na + Cl2 --> 2 NaCl

Step 1: Find out moles of Na and Cl to determine the limiting reactant:

moles Na = 12/23 = 0.52 moles Na

moles Cl2 = 16/71=0.225 moles Cl2

ratio Na:Cl is 2.3:1 so Cl is the limiting reactant.

Step 2: How many moles of NaCl are formed:

moles NaCl = moles Cl2 x (1 mol NaCl/2 moles Cl2) = 0.225/2 = 0.1125 moles NaCl

Step 3:

mass NaCl = moles NaCl x MM NaCl = 0.1125 x 58.45 = 6.576 g NaCl

Answer:

Absolute error in measurement of A = 0.3

Absolute error in measurement of B = 0.3

Explanation:

Absolute error is a measure of the amount of error in a measurement i.e. a measure of how far away a measurement is from a true value or an indication of the uncertainty in a measurement.

The Absolute Error is the difference between the actual and measured value. In formula, the absolute error, Δx is given as:

Δx = |xi – x|,

Where:  xi is the measurement, x is the true value,

| | indicates that only absolute values are taken

In the measurements by the student in the question:

Metal Cylinder A

measured value = 12.4 grams

actual mass of metal cylinder A = 12.7 g

Using the absolute error formula; Δx = |xi – x|

Absolute error in measurement of A = |12.4 - 12.7| = 0.3

Metal Cylinder B

measured value = 75.4 grams

actual mass of metal cylinder B = 75.1 g

Using the absolute error formula; Δx = |xi – x|

Absolute error in measurement of B = |75.4 - 75.1| = 0.3

Answer:

439.7nm

Explanation:

Energy of a quantum can be calculated using below formula

E=hv...........eqn(1)

But v=λ/ c .........eqn(2)

If we substitute eqn(2) into eqn(1) we have

E= hc/(λ)

Where E= energy

h= Plank's constant= 6.62607004 × 10-34 m2 kg / s

c= speed of light

c= 2.998 × 10^8 m/s

λ= wavelength= ?

But the energy was given in Kj , it must be converted to Kj/ photon for unit consistency.

Energy E= 272 kJ/mol × 1mol/6.02× 10^23

Energy= 451.83× 10^-24 Kj/ photon

E= hc/(λ)...........eqn(1)

If we make λ subject of the formula

λ= hc/E

Then substitute the values we have

λ= [(6.626 × 10^-34) × (2.998 × 10^8)]/451.83× 10^-24

λ=(0.00043965) × (1Kj/1000J) × (10^9nm/1m)

λ=439.7nm

Hence, the longest wavelength of radiation with enough energy to break carbon-sulfur bonds is 439.7nm

Solution

The mole is the number of particles contained in a substance

1 mol = 6.02.10²³

Moles can also be determined from the amount of substance mass and its molar mass

mol = mass : molar mass

mass = mol x molar mass

Molar mass = 58,6934 g/mol

Input the value :

mass = 0.0321 x 58,6934 g/mol

mass = 1.884 g

Answer:

The answer is "[tex]\bold{263 \ and \ 137.1 \frac{g}{ mol}}[/tex]".  

Explanation:

The chemical formula for Salicylamide: [tex]C_7H_7NO_2[/tex]

[tex]\to (12.011 \ \frac{g}{mol} \times 7)+(1.008 \ \frac{g}{mol} \times 7)+(14.0067 \frac{g}{mol} \times 1)+(15.999 \frac{g}{mol} \times 2) \\\\\to (84.077 \ \frac{g}{mol} )+(7.056 \ \frac{g}{mol} )+(14.0067 \frac{g}{mol})+(31.998 \frac{g}{mol} ) \\\\\to (84.077 \ \frac{g}{mol} )+(7.056 \ \frac{g}{mol} )+(14.0067 \frac{g}{mol})+(31.998 \frac{g}{mol} ) \\\\ =137.1377 \approx 137.1\ \frac{g}{mol}[/tex]

The chemical formula of Iodosalicylamide:[tex]C_7H_6INO_2[/tex]

[tex]\to (12.011\frac{g}{mol}\times 7)+(1.008\frac{g}{mol}\times 6)+(126.904\frac{g}{mol}\times 1)+(14.0067\frac{g}{mol}\times 1)+(15.999\frac{g}{mol}\times 2) \\\\\to (84.077\frac{g}{mol})+(6.048\frac{g}{mol})+(126.904\frac{g}{mol})+(14.0067\frac{g}{mol})+(31.998\frac{g}{mol}) \\\\=263.0337 \approx 263.0\ \frac{g}{mol}[/tex]

Answer:

monosaccharides and glycosidic, I think

Explanation:

Answer:

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Explanation:

edi wow

Answer:

Nickel

Explanation:

Given data:

Density of iron = 7.9 g/cm³

Density of lead = 11.3 g/cm³

Density of nickel = 8.9 g/cm³

Mass of sample = 134 g

Volume of sample = 15 cm³

Which metal it is = ?

Solution:

First of all we will calculate the density of sample and then match it with the density of given metals.

Formula:

d = m/v

by putting values,

d = 134 g/ 15 cm³

d = 8.9 g/cm³

The weighted sample is nickel metal.

Answer:

Explanation:

4 Li(s) + 1 O2(g) -> 2 Li2O(s)

To calculate the atoms of an element in a given molecule, we need to multiply stoichiometry by the number that is written on the foot of that element. Therefore, the balanced equation is 4 Li(s) + 1 O[tex]_2[/tex](g) [tex]\rightarrow[/tex] 2 Li[tex]_2[/tex]O(s).

Balanced equation is the one in which the total number of atoms of a species on reactant side is equal to the total number of atoms on product side. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, displacement reaction.

The other characteristic of balanced reaction is that physical state should be written with each compound or molecule on reactant and product side. Physical state should be written in brackets. s means solid, l means liquid, g means gas. The balanced equation for the given reaction is 4 Li(s) + 1 O[tex]_2[/tex](g) [tex]\rightarrow[/tex] 2 Li[tex]_2[/tex]O(s)

Therefore, the balanced equation is 4 Li(s) + 1 O[tex]_2[/tex](g) [tex]\rightarrow[/tex] 2 Li[tex]_2[/tex]O(s).

Learn more about the balanced equation, here:

https://brainly.com/question/7181548

#SPJ2

Answer:

products

Explanation:

yeah the answer is product

Answer:

law of multiple proportions

Explanation:

The law of multiple proportions states that, if two elements A and B, combine to form more than one chemical compound. Then the various masses of one element A, which combine separately with a fixed mass of element B are in  simple multiple ratio.

We can see that the ratio of oxygen that combines with carbon in the two compounds( A and B) is 1:2. This demonstrates the law of multiple proportions.

The substances A and B must be CO and CO2 respectively.

Explanation:

w is the stage in which dna is copied and cell grows.

Answer:

w

Explanation:

Chief Keef - Love Sosa

Answer:

an aquifer is a renewable resource

Explanation:

Aquifers are defined as the groundwater found deep in the layers of rocks.

An aquifer is considered as a renewable resource because groundwater is renewed over time. Aquifers are water resources and follow hydrological cycle through which it can renew itself.

Some of the deep aquifers are considered as  nonrenewable resource because it toll hundreds of years to accumulate.

Hence, the correct answer is yes an aquifer is a renewable resource except some deep aquifers.

Answer:

See answer below

Explanation:

a.) Lithium Chloride, LiCl is soluble in water.

b.) Silver Chloride, AgCl is insoluble in water.

c.) Barium Carbonate, BaCO3 is insoluble in water.

d.)Potassium, K2 is soluble in water.

e.) Iron (III) Nitrate Fe(NO3)3 is soluble in water.

Mass O2 = = 16.832 g

Given

43 grams of potassium chlorate

Required

Mass of O2

Solution

Reaction

2KClO3 ⇒3O2 + 2KCl

Mol KClO3 :

= mass : MW

= 43 g : 122,55 g/mol

= 0.3509

From the equation, mol O2 :

= 3/2 x moles KClO3

= 3/2 x 0.3509

= 0.526

Mass O2 :

= 0.526 x 32 g/mol

= 16.832 g

The daughter isotope  : Radon-222 (Rn-222).

Given

Radium (Ra-226) undergoes an  alpha decay

Required

The daughter nuclide

Solution

Radioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,  

The decay reaction uses the principle: the sum of the atomic number and mass number before and after decay are the same

Radium (Ra-226) : ₈₈²²⁶Ra

Alpha particles : ₂⁴He

So Radon-226 emits alpha α particles ₂He⁴  , so the atomic number decreases by 2, mass number decreases by 4

The reaction :

₈₈²²⁶Ra ⇒ ₂⁴He + ₈₆²²²Rn

Answer:

the invention of the microscope has made seeing bacteria/cells, examining forensic evidence (such as fingerprints), studying atomic structure, tissue analysis, and the study of our ecosystem possible to the naked eye

Explanation:

hope this helps

Answer:

atoms

Explanation:

i hope that help you

Answer:

atoms

Explanation:

Answer:

32 days.

Explanation:

First we determine how much is made in a day.

16.50 x 4 = 66.

Next, we divide 2100 by 66 to reach our amount of days needed.

2100 / 66 = 31.818181... [81 is what repeats over and over.]

We round this up to the nearest whole number. You can't underpay, so you have to round.

The next whole number would be 32, so our answer is 32 days.

Answer:

one mole of oxygen will produce [tex]0.4[/tex] moles of water

Explanation:

The balanced chemical reaction is as follows -

2 C2H2 + 5 O2 --> 4 CO2 + 2 H2O

As we can see in this reaction

5 mole of oxygen (on the reactant side) will produce 2 mole of water (on the product side)

Hence, one mole of oxygen will produce [tex]\frac{2}{5} =0.4[/tex] moles of water

Answer:

No. of moles = 0.0685

Explanation:

Given mass, m = 15.5g

We need to find the number of moles in 15.5 g of CaSO₄.5H2O

First, we find the mass of CaSO₄.5H2O.

M = (1×40)+(1×32)+(4×16)+(5×18)

M = 226 g/mol

We know that,

Number of moles = given mass/molar mass

[tex]n=\dfrac{15.5\ g}{226\ g/mol}\\\\n=0.0685\ \text{mol}[/tex]

Hence, there are 0.0685 moles in 15.5 g of CaSO₄.5H2O.

Answer:

See explanation below

Explanation:

In this case, we can use the Boyle's law. Assuming that the temperature of both trial remains constant, then:

P₁V₁ = P₂V₂    (1)

You should note that this expression is usable when you are dealing with gases. However, we can treat this unknown liquid as a gas, because all the air on the flask is removed, and we can assume that the liquid can behave like an ideal gas.

So using the above expression, we can solve for P₂:

P₂ = P₁V₁ / V₂    (2)

In this case, we already have the values of presures and volume, so replacing in this expression:

P₂ = 34.5 * 5 / 214

This should be the pressure of the liquid.

Hope this helps

Answer:

The mouth uses both mechanical and chemical digestion. Mechanical digestion involves physically breaking down the food into smaller pieces (using the jaw/teeth). However, chemical digestion then takes over and starts breaking down the food into simpler nutrients that can be used by the cells using saliva, which is naturally made within the mouth.

Hope this helps you! Have a great day! :D

the answer Is A hope it helps