You are attempting the reduction of quinone with sodium borohydride. After adding the 0.05 g of NaBH4 you note that the solution remains yellow. Following the procedure, you continue to add increments of 0.05 g NaBH4. You note that the yellow color remains even after the addition of 0.10 g of extra NaBH4. Several students around you are experiencing a similar problem. Propose a cause for this and suggest a solution.

Answer:

A chemical bond holds atoms together.

Answer:

14.25g

Explination:

I found this answer on quizlet titled, "Chem Quizlet" by jamie_barbara

Answer:

A mole ratio is ​the ratio between the amounts in moles of any two compounds involved in a chemical reaction.

Mole ratios are used as conversion factors between products and reactants in many chemistry problems.

Explanation:

Answer:

ΔHreaction (KJ) =  - 78 KJ

The value may vary in relation to the source of the bond enthalpy data.

 Bond enthalpies used  (From a table of bond enthalpies )

Bond           KJ/ mol

C≡O           1080

C-Cl            330

C=O           741

Cl-Cl           243

Explanation:

                         CO(g) + Cl2(g)  →    COCl2(g)

1) Lewis structures

Valence electrons

C     4

O     6

Cl     7

Reactants

CO(g)

In the case of CO, carbon has a negative charge and oxygen a positive charge.

Cl2(g)

Products

COCl2(g)

_______________________

ΔHreaction (KJ) = ∑ n* ΔH ( reactants) - ∑ n* ΔH (product)

ΔHreaction (KJ) =   (ΔHC≡O +   ΔHCl-Cl)  - ( ΔHC=O  + 2* ΔHC-Cl)

Replacing the values

ΔHreaction (KJ) =   (1080 +  243)  - ( 741 + 2* 330)

ΔHreaction (KJ) = 1323 -  1401

                          =  - 78 KJ

Answer:

Explanation:

Do a quick conversion: 1 grams H3PO4 = 0.010204583427424 mole using the molecular. How many grams H3PO4 in 1 mol?  You can view more details on each measurement unit: molecular weight of H3PO4 or mol This. The formula weight is simply the weight in atomic mass units of all the atoms in a given formula.

Answer:

If you mix equal amounts of a strong acid and a strong base, the two chemicals essentially cancel each other out and produce a salt and water. Mixing equal amounts of a strong acid with a strong base also produces a neutral pH (pH = 7) solution.

Answer:

The sample of __Ca___ contains the greatest number of atoms

Explanation:

As we know,

1 mole [tex]= 6.022*10^{23}[/tex] molecular entities (Can be atom, ions or molecules)

Number of atoms in 1.76 mole sample of Be

[tex]= 6.022*10^{23} *1.76\\= 1.059 * 10^{24}[/tex]

The sample of __Ca___ contains the greatest number of atoms

Answer:

A. 2 : 13

B. 10 : 13

C. 10 moles of water, H₂O.

D. 2 moles of butane, C₄H₁₀

E. 116 g of butane, C₄H₁₀

F. 13 moles of oxygen, O₂

G. 416 g of oxygen, O₂

Explanation:

The equation for the reaction is given below:

2C₄H₁₀ + 13O₂ —> 8CO₂ + 10H₂O

A. Determination of the mole ratio between butane and oxygen gas.

Mole of butane, C₄H₁₀ = 2 moles

Mole of oxygen, O₂ = 13 moles

Mole ratio of butane and oxygen = 2 : 13

B. Determination of the mole ratio between water and oxygen gas

Mole of the water, H₂O = 10 moles

Mole of oxygen, O₂ = 13 moles

Mole ratio of water and oxygen = 10 : 13

C. Determination of the moles of water formed.

From the balanced equation above,

10 moles water, H₂O were produced.

D. Determination of the moles of butane burned.

From the balanced equation above,

2 moles of butane, C₄H₁₀ were burned.

E. Determination of the mass of butane burned.

Molar mass of C₄H₁₀ = (12×4) + (10×1)

= 48 + 10 = 58 g/mol

Mole of C₄H₁₀ = 2 moles

Mass of C₄H₁₀ =?

Mass = mole × molar mass

Mass of C₄H₁₀ = 2 × 58

Mass of C₄H₁₀ = 116 g

Thus, 116 g of butane, C₄H₁₀ were burned.

F. Determination of the number of mole of oxygen used.

From the balanced equation above,

13 moles of oxygen, O₂ were used.

G. Determination of the mass of oxygen used.

Molar mass of O₂ = 2 × 16 = 32 g/mol

Mole of O₂ = 13 moles

Mass of O₂ =?

Mass = mole × molar mass

Mass of O₂ = 13 × 32

Mass of O₂ = 416 g

Thus, 416 g of oxygen, O₂ were used.

Answer:

The trench.

Explanation:

A region where this process occurs is known as a subduction zone, and its surface expression is known as an arc-trench complex.

Answer:

Prism B

Explanation:

Answer:

It getting darker

Explanation:

This is because the light isn't hitting the earth as much, making it darker. They might also see more city lights than before. Hope this helps! plz mark as brainliest!

Answer:

Average atomic mass = 32.057 u

Explanation:

Average atomic mass = Σ(isotope × abundance)

Average atomic mass = (0.95 × 31.972) + (0.0076 × 32.971) + (0.0422 × 33.967)

Average atomic mass = 32.057 u

Answer:

B: Covalent bond and Ionic bond

The sun contained 99% of the available matter and the rest matter formed smaller clumps inside the spinning disk. These clumps gained enough mass which lead to their gravity shaping them into spheres becoming planets.

A planet can be described as a large, rounded astronomical body that is neither a star nor its remnant. The theory of planet formation is the nebular hypothesis, which tells that an interstellar cloud collapses out of a nebula to generate a young protostar orbited by a protoplanetary disk.

The planet grows in this disk by the accumulation of material driven by gravity and this process is known as accretion. Our solar system has at least eight planets that rotate around an axis tilted with respect to its orbital pole.

All planets possess an atmosphere, although that of Mercury is tenuous.  The Solar System planets create magnetic fields apart from Venus and Mars, and all planets except Venus and Mercury have natural satellites.

Learn more about planets, here:

https://brainly.com/question/15268075

#SPJ2

Answer:

160 mol H₂O

Explanation:

Step 1: Write the balanced complete combustion reaction

CH₄ + 2 O₂ ⇒ CO₂ + 2 H₂O

Step 2: Establish the appropriate molar ratio

According to the balanced equation, the molar ratio of CH₄ to H₂O is 1:2.

Step 3: Calculate the moles of water formed from 80 moles of methane

We will use the previously established molar ratio.

80 mol CH₄ × 2 mol H₂O/1 mol CH₄ = 160 mol H₂O

Answer:

The answer is "[tex]\bold{HClO_3 > HClO_2 >HClO > HBrO}[/tex]"

Explanation:

We arrange oxoacids to decrease the intensity of acids in this question. Or we may conclude all this from strongest to weakest acids they order oxoacids, that's why above given order is correct.

Answer: 24g

Explanation:

Answer:

20.2 amu.

Explanation:

Let A represent isotope ²⁰X

Let B represent isotope ²²X

From the question given above, the following data were obtained:

For Isotope A (²⁰X):

Mass of A = 20

Abundance (A%) = 90%

For Isotope B (²²X):

Mass of B = 22

Abundance (A%) = 10%

Relative atomic mass (RAM) =?

The relative atomic mass (RAM) of the element can be obtained as follow:

RAM = [(Mass of A × A%)/100] + [(Mass of B × B%)/100]

RAM = [(20 × 90)/100] + [(22 × 10)/100]

RAM = 18 + 2.2

RAM = 20.2 amu

Thus, relative atomic mass (RAM) of the element is 20.2 amu

Answer:

The correct answer is - so that other scientists can replicate the experiment and make sure the results are correct or to check accuracy.

Explanation:

The data and procudres are required to be recorded or noted correctly so the experiment and research can be replicate and tested for the accuracy of the experiment by other scientist and researcher.

Mandy also need to note procedure, data, variables and other data correctly for the testing the accuracy and replication of the experiment. The replication is essential to check if every thing is correct and result are error free.

Answer:

I didn't do anything, we don't celebrate lol I hope you had fun though!

Explanation:

As the atomic number increases, the reactivity of the halogens decreases. Fluorine and chlorine exist as gases at room temperature, while bromine is a liquid, and iodine is a solid.

Answer:

As the atomic number increases, the reactivity of the halogens decreases. Fluorine and chlorine exist as gases at room temperature, while bromine is a liquid, and iodine is a solid.

Answer:

Explanation: Sodium Nitroprusside, whose molecular formula is  • 2H2O, and whose molecular weight is 297.95. Dry sodium nitroprusside is a reddish-brown powder, soluble in water.

Explanation:

it has different temperature but uniform humidity

hope it will help you

Answer: d

Explanation: took the test got it right

Answer:

2 L

Explanation:

From the question

Applying boyles law,

PV = P'V'....................... Equation 1

Where P = Initial pressure, P' = Final Pressure, V = Initial Volume, V' = Final Volume.

make V' the subject of the equation

V' = PV/P'.................... Equation 2

Givne: V = 5 L, P = 500 mmHg, P' = 1240 mmHg

Substitute these values into equation 2

V' = (5×500)/1240

V' = 2500/1240

V' = 2 L

I haven't done these in some time, so I'm not sure if they are 100% right.

1) 6.3 moles of H2( 2 mol of NH3 / 3  mol of H2)= 4.2 mol of NH3

6.3 moles of H2( 2 mol of NH3/ 3 mol of H2)(17.04 g of NH3/1 mol NH3)= 71.57 g of NH3

2) 2.5 moles of N2(2 mol of NH3/1 mol of N2)= 5 moles of NH3

2.25 moles of N2(2 mol of NH3/ 1 mol of N2)(6.02x10^23 particles/ 1 mol of NH3)= 3.01x10^24 particles of NH3

3) 425 g of NH3(1 mol of NH3/17.04 g NH3)= 24.9 moles of NH3

425 g of NH3(1 mol of NH3/17.04 g of NH3)(1 mol of N2/2 mol of NH3)(28.02 g of N2/1 mol N2)= 349 g of N2

425 g of NH3(1 mol of NH3/17.04 g of NH3)(1 mol of N2/2 mol of NH3)= 12.5 mol of N2

4) 10 moles NH3(3 moles of H2/2 moles of NH3)= 15 moles H2

10 moles NH3(3 mol of H2/2 mol of NH3)(2.02 g of H2/1 mol of H2)= 30.3 g of H2

30.3 g = .0303 liters of H2

Answer:

see below

Explanation:

1)  chem rxn    compound   molecule   covalent   ions    ionic

2) 2 hydrogen  one oxygen       H2O    covalent

3) is always liq