the normal human eye responds to visible light of wavelength range from about 390 to 710nm. Determine the frequency range of the human eye.​

Answer:

In Homogenous mixtures, the whole mixture is in the same phase whereas in Heterogeneous mixture, substances can be of two phases and layers may separate. ... Homogeneous mixture could be exemplified as a sugar solution or salt solution whereas Mixture of salt and sand could be used as an example of Heterogeneous mixture.

Answer:

A

Explanation:

The trick here is to know what the conservation of mass means.

It means that no matter what happens and how much change there is, the mass of the carbons on the reactants = the mass of the carbons on the products.

That's exactly what A says.

Answer:

resultant

Explanation:

The mass of ammonium chloride that must be added is : ( A ) 4.7 g

Given data :

Volume of water ( V )  = 250 mL = 0.25 L

pH of solution = 4.85

Kb = 1.8 * 10⁻⁵

Kw = 10⁻¹⁴

Given that the dissolution of NH₄Cl gives NH₄⁺⁺ and Cl⁻ ions the equation is written as :

NH₄CI  +  H₂O  ⇄  NH₃ + H₃O⁺

where conc of H₃O⁺

[ H₃O⁺ ] = [tex]\sqrt{Ka.C}[/tex]   and Ka = Kw / Kb

∴ Ka = 5.56 * 10⁻¹⁰

Next step : Determine the concentration of H₃O⁺  in the solution

pH = - log [ H₃O⁺ ] = 4.85

∴ [ H₃O⁺ ] in the solution = 1.14125 * 10⁻⁵

Next step : Determine the concentration of NH₄CI in the solution

C = [ H₃O⁺ ]² / Ka

  = ( 1.14125 * 10⁻⁵ )² /  5.56 * 10⁻¹⁰

  = 0.359 mol / L

Determine the number of moles of NH₄CI in the solution

n = C . V

  = 0.359 mol / L  * 0.25 L =  0.08979 mole

Final step : determine the mass of ammonium chloride that must be added to 250 mL

mass = n * molar mass

         = 0.08979 * 53.5 g/mol

         = 4.80 g  ≈ 4.7 grams

Therefore we can conclude that the mass of ammonium chloride that must be added is 4.7 g

Learn more about ammonium chloride : https://brainly.com/question/13050932

Explanation:

What do you mean by 'how many oxygen'?

oxygen atoms? or oxygen percentage?

if oxygen atoms is 12 atoms

c)

)

Na + Mg2+

Na + Mg

Na=

Mg =

=

Zn + CO2-

Zn?- + Co

Zn =

Co=

Answer:

liquid and gas........................

Answer:

It increases the freezing point

Explanation:

The salt lowers the temperature at which water freezes. :)

I believe the answer would be D

Answer:

HS(-)

HCOO(-)

SO3(2-)

SO4(2-)

S(2-)

NO2(-)

CN(-)

Explanation:

The parenthesis are the charges of the compounds. When an acid is introduced in a base, it dissociates its Hydrogens giving protons to the base. In this case, if you remove one hydrogen of a compound, you will reduce the charge of a compound since basically you're removing a positive charge from a compound. If you need to, I can explain how the thing of the charges work.

In fact, the definition of a conjugate base is a compound created when the original (an acid) compound dissacioate an atom of hydrogen (a proton) in a base.

Answer:

What is nanofluids?

Nanofluids are engineered suspensions of nanometer-sized solid particles in a base fluid. Suspending small solid particles in the energy transmission fluids can improve their thermal conductivity and provides an effective and innovative way to enhance their heat transfer characteristics significantly.

How nanofluids work?

Nanofluid refers to the dispersion of metal or non-metal nano-powder into traditional heat exchange media such as water, alcohol, and oil to prepare a uniform, stable and high thermal conductivity. The traditional heat exchange medium has a low thermal conductivity and has been unable to meet the growing demand for industrial engineering heat exchange. The thermal conductivity of some metal or non-metal nanoparticles is often hundreds of times higher than that of heat-conducting media. For example, common silicon carbide nanoparticles have a thermal conductivity of 170-270 W/m•K. The researchers found that if the nanoparticles can be uniformly and stably dispersed in the heat transfer medium, the thermal conductivity of the nanoparticles will be greatly improved.

Answer:

Q= ms∆T

Where, m is mass of substance

S is specific heat

∆T is temperature change

As in question , m=8.21 ,s=0.13 ,∆T =6.2

So, Q = 8.21×0.13×6.2=6.61 J

Answer:

1.1 mol

Explanation:

n=m/M, where n is moles, m is mass, and M is molar mass.

M of CO2 = 12.01+16.00+16.00 = 44.01g/mol

n=50g/44.01g/mol

n = 1.13610543 mol

n ≈ 1.1 mol

Hope that helps

Answer:

His kinetic energy is converted into potential energy.

Explanation:

Answer:

0.001742moles

Explanation:

1000ml of NaOH contain 0.1moles

17.42ml of NaOH contain (0.1*17.42)/1000 moles

= 0.001742moles

Answer:

The egg will gain mass.

Explanation:

Eggs soaked in distilled water will gain mass and appear dramatically swollen.

Answer:

Gain mass

Explanation:

Carbonated water will create a reaction inside the egg making the fluid inside the egg becoming more solid thus gaining mass

Hope this helps!

Answer:

5-3. Ice water 0 "C. A steel tank contains carbon dioxide at 27 "C and a pressure of 12.0 atm.

Explanation:

True, the entropy of a perfectly ordered crystalline substance at 0 K is 0 J/mol.

The third law of thermodynamics states that, the entropy of a system approaches a constant value as the temperature of the system approaches absolute zero.

The entropy of any perfectly ordered, crystalline substance at absolute zero temperature is zero.  That is, the entropy of a pure, perfect crystalline substance at 0 K is 0 J/K.

Thus, we can conclude that the given statement is true.  The entropy of a perfectly ordered crystalline substance at 0 K is 0 J/mol.

Learn more about third law of thermodynamics here: https://brainly.com/question/1156831

Answer:

What is the number of moles of carbon present in 44 grams of carbon dioxide? One. 44 grams is a mole of carbon dioxide and there is one carbon atom in CO 2 so there is one mole of carbon. That’s how chemistry works.

Explanation:

What is the number of moles of carbon present in 44 grams of carbon dioxide? One. 44 grams is a mole of carbon dioxide and there is one carbon atom in CO 2 so there is one mole of carbon. That’s how chemistry works.

Answer:

it's non-spontaneous

Explanation:

I hope it helps you

Answer:

D

Explanation:

The valence electrons are the outer electrons and must be located in the outermost shell. In this case, D.

Answer:

it is in the same phase as the reactants

The  statement describes a homogeneous catalyst is,

So, option B is correct one.

The substance which increases the rate of the reaction without being itself change at the end of the reaction is called catalyst.

learn about homogeneous catalyst,

https://brainly.com/question/4249142

#SPJ2

Answer:

Yes

Explanation:

You can tell because there are 2 moles of H2 on the reactants side and 1 mole of O2, and on the products side we see the same amount, meaning that no moles of H2 or O2 were added or destroyed, meaning that it follows the law of conservation of matter.

Equilibrium concentration of HOCl at 25°C is 0.140 M

The equation of the reaction at equilibrium is given below:

H₂O (g) + Cl₂O (g) ⇄ 2 HOCl (g)

Equilibrium constant, Kc = 0.0900 at 25°C

An ICE chart for the reaction is set up below

     H₂O (g)  +  Cl₂O (g)   ⇄  2 HOCl (g)

I     0.384        0.384             0.652

C     -x                -x                   + 2x

E    0.384 - x   0.384 - x       0.652 + 2x

The equation of the equilibrium constant is given as;

Kc = [tex]\frac{[HOCl]^2}{[H_{2}O][Cl_{2}O]}[/tex]

substituting the values into the equation:

Kc = [tex]\frac{(0.652 + 2x)^2}{( 0.384 - x)( 0.384 - x)}[/tex] = 0.0900

4x² + 2.608x + 0.425 = 0.0900 (0.147 - 0.768x + x²)

4x² - 0.09x² + 2.677x - 0.069x + 0.425 - 0.013 = 0

3.910x² + 2.677x + 0.412 = 0

Solving using the quadratic formula:

a = 3.910, b = 2.677, c = 0.412

x = [tex]\frac{-2.677\±\sqrt{2.677^2 - 4*3.910*0.412}}{2*3.910}[/tex]

x = -0.256 or -0.431

The negative sign indicates that equilibrium is to the left of the reaction

Since x cannot be greater than 0.384, x = -0.256.

Equilibrium concentration of HOCl = 0.652 + 2(-0.256)

Equilibrium concentration of HOCl at 25°C is 0.140 M

Learn more at: https://brainly.com/question/15050697

The elements in the lanthanide series are similar to gadolinium.

The periodic table is arranged in groups and periods. Elements in the same group have similar properties. At the bottom row of the periodic table lies a group of elements that have unique properties called the lanthanides. This is where Gadolinium belongs.

The elements in the lanthanide series such as europium and terbium are similar to gadolinium. The lanthanides are similar in chemical reactivity and appearance. However, the density of the metals differ because it increases with increase in atomic number.

Learn more: https://brainly.com/question/1415109

Answer:

6.022 × 1023

Explanation:

1 mole of H:

The definition of Avogadro's number of 6.022 × 1023/mole is the number of atoms or molecules per one gram atomic weight. For one gram atomic weight of hydrogen with an atomic weight of one gram, one mole of hydrogen contains 6.022 × 1023 hydrogen atoms. 1.45⋅6.02⋅1023≈8.73⋅1023 hydrogen atoms.

1 mole:

The value of the mole is equal to the number of atoms in exactly 12 grams of pure carbon-12. 12.00 g C-12 = 1 mol C-12 atoms = 6.022 × 1023 atoms • The number of particles in 1 mole is called Avogadro's Number (6.0221421 x 1023).

in an H:

H: 2×2×4=16 atoms of hydrogen. C: It only appears once and without a subscript, so 1×4=4 .  O : Like carbon, it's 1×4=4 .

1.00 mole:

One mole is equal to 6.02214179×1023 atoms, or other elementary units such as molecules.

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Answer: it wound'nt let me type the equations out so i did it on g.o.o.gl.e docs :')

Explanation:

hope this helps <3

have a great day/night/noon

:)