The diagram shows the electron configuration around the chlorine nucleus. Chlorine has 17 protons.
CI
Which of the following correctly completes the statement?
Chlorine has valence electrons, and the effective nuclear charge, Zett, for the chlorine atom shown is
O A. 7,7+
OB. 7,7-
O C. 10,7-
D. 17, 7+

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:

215.9 cm

Explanation:

1 foot= 30.5cm

30.5cm times 7 1/12=215.9cm

The given height of David is 7 ft, 1.0 inch, so in centimeters, the height will be 216.4 cm.

A conversion factor is a number that is used to multiply or divide one set of units into another. When converting to an equal value, the appropriate conversion factor must be used.

We must convert one unit to another in order to achieve accuracy and avoid measurement confusion.

We do not, for example, measure the length of a pencil in kilometers. In this case, one must convert kilometers (km) to centimeters (cm) (cm).

To convert feet to centimeters, multiply the given foot length by 30.48 cm.

So,

Height in cm will be = 7.1 x 30.48

Height in cm = 216.4cm

Thus, the height of David in centimeters is 216.4 cm.

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Answer:

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According to the concept of Avogadro's number, there are 29.056×10²³ molecules in 77.2 g of methane.

Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.

It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .

According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.

Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number

In the given example, number of moles=77.2/16=4.825 moles

If 1 mole has 6.023×10²³ molecules , then 4.825 moles will have 4.825×6.023×10²³ /1=29.056×10²³ molecules .

Thus, there are 29.056×10²³ molecules in 77.2 g of methane.

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Answer:

369 ml

Explanation:

Mass of Aluminium (Al) = 20 g

Molar concentration =  2.007M

Molar concentration = Number of moles / Volume

The relationship between mass and number of moles;

Number of moles = Mass / Molar mass

Number of moles = 20 / 27 = 0.741 mol

2.007  = 0.741  / Volume

Volume = 0.741 / 2.007 = 0.369 L

converting to millilitres by multiplying by 1000

Volume = 0.369 * 1000 = 369 ml

Answer:

[tex]k_2=2.46[/tex]

Explanation:

Hello!

In this case, according to the Arrhenius equation for variable temperature:

[tex]ln(\frac{k_2}{k_1} )=-\frac{Ea}{R}(\frac{1}{T_2} -\frac{1}{T_1} )[/tex]

Given the temperatures to be computed in kelvins and the activation energy, we obtain:

[tex]ln(\frac{k_2}{0.924} )=-\frac{89800J/mol}{8.314J/(mol*K)}(\frac{1}{306.45K} -\frac{1}{298.15K} )\\\\ln(\frac{k_2}{0.924} )=0.981\\\\k_2=0.924*exp(0.981)\\\\k_2=2.46[/tex]

Best regards!

Answer:

68.1% is percent yield of the reaction

Explanation:

The reaction of methane with oxygen is:

CH₄ + 2O₂ → CO₂ + 2H₂O

Where 2 moles of oxygen react per mole of CH₄

Percent yield is:

Actual yield (28.2g CO₂) / Theoretical yield * 100

To solve this question we need to find theoretical yield finding limiting reactant :

Moles CH₄:

15.1g CH₄ * (1mol / 16.04g) = 0.9414 moles

Moles O₂:

81.2g * (1mol / 32g) = 2.54 moles

For a complete reaction of 0.9414 moles of CH₄ are needed:

0.9414 moles CH₄ * (2 mol O₂ / 1mol CH₄) = 1.88 moles of O₂. As there are 2.54 moles, O₂ is in excess and CH₄ is limiting reactant

In theoretical yield, the moles of methane added = Moles of CO₂ produced. That is 0.9414 moles CO₂. In grams = Theoretical yield:

0.9414 moles CO₂ * (44.01g / mol) = 41.43g CO₂

Percent yield: 28.2g CO₂ / 41.43g CO₂ * 100=

Answer:

hydrogen

Explanation:

In electrolysis of water, gas evolved at cathode is hydrogen

Answer: 1075.5 mph

Explanation:anything moving at 4.78*10^4 cm/sec

equivalent to

cm —> miles = 1/1.6*10^5

sec —> hr = 1/3600

[4.78*10^4]*3600/1.6*10^5 = 1075.5 mph

Answer:

Measure the volume of water poured into a graduated cylinder, then place the object in the water and remeasure the volume. The difference between the two volume measurements is the volume of the object. Now simply divide the mass by the volume to calculate the density of the object.

Answer: C ) The reactants are higher in energy than the products

Explanation:

The enthalpy that is a state variable that identifies the content of heat. Then the change of enthalpy for the exothermic reactions is negative, meaning that the energy of the products is lower than the energy of the reactants.

Answer:

any gas takes up 22.4L per mole so 2.4*22.4=53.76

Explanation:

In 2.4 moles at STP, 53.79 litres of N2 gas are present.

Moles are defined as the amount of substance of a system that contain the same number of entities as the number of atoms in 12g of carbon 12.

STP is defined as the standard temperature and pressure. At STP, as system has s temperature of zero degree centigrade or 273 Kelvin and the pressure is 1 atm.

PV= nRT

P= 1 atm

V= ?

n= 2.4 moles

R= 0.0821 L atm /K/mol

1 x V = 2.4 x 0.0821 x 273

V = 53.79 litres

Hence, 53.79 litres of N2 gas is present in 2.4 moles at STP.

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indicator, hope this helps :

Answer:

B

Explanation:

Because that's what is being changed into a different color.

Answer:

More exactly this number is 6.02 x 1023 10 2 3 .

Answer:

90 mV

Explanation:

Faraday constant, F = 96487

Gas constant, R = 8.314

Number of mole of electron transferred, Z = 2

MgCl in solution A, = 0.1 mm

MgCl in solution A, = 100 mm

Using the relation :

E=(RT/ZF) In(Mg out/Mgin)

E = (8.314*298) / (2*96485) * In(100/0.1)

E = (2477.572 / 192970) * 6.9077552

E = 0.0128391 * 6.9077552

E = 0.0886897 V

E = 88.68 mV (approximately 90 mV)

Answer:

Density, d = 5.96 g/mL

Explanation:

Given that,

Mass, m = 105 g

Volume, V = 17.6 mL

We need to find the density of the substance. So,

[tex]d=\dfrac{m}{V}\\\\d=\dfrac{105\ g}{17.6\ mL}\\\\d=5.96\ g/mL[/tex]

So, the density of the substance is 5.96 g/mL.

Answer:

44.84 ml

Explanation:

14.86

+

15.0

+

14.980

_______

44.84

Answer:

Hope this help you

Explanation:

The answer is 261.3368. We assume you are converting between grams Barium Nitrate and mole. You can view more details on each measurement unit: molecular weight of Barium Nitrate or mol The molecular formula for Barium Nitrate is Ba(NO3)2.

Answer:

0.382

Explanation:

Answer:

i wish i know

Explanation:

i wish i know

Answer:

0.847 molecule.

Explanation:

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

Mass of X₄Z₃ = 3.93×10¯²² g

Number of molecules of X₄Z₃ =?

Avogadro's number = 6.022×10²³ molecules

Next, we shall determine the molar mass of X₄Z₃. This can be obtained as follow:

Molar mass of X₄Z₃ = (4×59.45) + (3×13.84)

= 237.8 + 41.52

= 279.32 g/mol

Finally, we shall determine the number of molecules in 3.93×10¯²² g of X₄Z₃. This can be obtained as follow:

From Avogadro's hypothesis,

1 mole of X₄Z₃ = 6.022×10²³ molecules

But 1 mole of X₄Z₃ = 279.32 g

Thus we can say that:

279.32 g = 6.022×10²³ molecules

Therefore,

3.93×10¯²² g = 3.93×10¯²² × 6.022×10²³ / 279.32

3.93×10¯²² g = 0.847 molecule.

Thus, 3.93×10¯²² g of X₄Z₃ contains 0.847 molecule.

Answer:

1 mole is equal to 1 moles Krypton, or 83.798 grams.

Explanation:

Answer:

[tex]APF(atomic packing factor)=0.31736[/tex]

Explanation:

From the question we are told that

Density of metal [tex]\rho=11.6 g/cm3[/tex]

Atomic weight of [tex]W=157.6 g/mol[/tex]

Atomic radius of [tex]r= 0.127 nm[/tex]

Lattice parameters=>[tex]x=0.523nm[/tex]  and [tex]y=0.330 nm[/tex]

Generally the equation for atomic packing factor is mathematically given as

[tex]APF(atomic packing factor)=\frac{Spere's\ volume}{unit\ cell\ volume}[/tex]

[tex]APF(atomic packing factor)=\frac{N*VN}{VC}[/tex]

Generally the equation for number of atoms N is mathematically given as

[tex]N=\frac{\rho }{atomic raduis*Avacados constant}[/tex]

[tex]N=\frac{11.6 }{0.127*10^{-9}*6.02214086*10^{23} mol-1}[/tex]

[tex]N=4[/tex]

Therefore APF(atomic packing factor)

[tex]APF(atomic packing factor)=\frac{N*VN}{VC}[/tex]

[tex]APF(atomic packing factor)=\frac{4*\frac{4}{3} \pi (0.127)^3}{(0.523)^2 *0.330}[/tex]

[tex]APF(atomic packing factor)=0.31736[/tex]

Answer:

What is ^ for?

Explanation:

Strong Acid: dissolves and dissociates 100% to produce protons (H+) 1. seven strong acids: HCl, HBr, HI, HNO3, H2SO4, HClO4, & HClO3 2. ... Weak Acid: dissolves but less than 100% dissociates to produce protons (H+) 1.

Answer:

1. False 2.True3.True? Unsure

Explanation: