What kinds of things can we learn by studying atoms?

How would you prepare 500 ml of a .50m solution of naoh from a 2 m stock solution

Bad White [126]

Explanation:

i.e M = m/V(L)

M= Molarity of substance

m = number of moles of substance (i.e solute)

V(L) = volume of solution in Litres

So talking about our question molarity should be 0.5 M,volume should be 0.1 L , and we should know that Molar Mass of NaOH is 40 because Atomic mass of Sodium i.e (Na known as Natrium) is 23,Atomic mass of Oxygen (O) is 16 and Atomic mass of Hydrogen is 1.

Adding them all up gives Molecular mass of NaOH as 40

So if we solve above equation we get no of moles of NaOH present in 0.1 litres of solution

Let’s do that math

Rearranging equation we get m=M×V(L) i.e m= 0.5×0.1 =0.05. So 0.05 moles of NaOH are present in 100 ml of 0.5 Molar solution

Now we also know that to find no of moles of a substance we have a formula and it is m=W/Mw where

m = no of moles of a substance

W = Mass of substance

Mw = Molecular weight of the substance

So substituting all values and rearranging equation we get mass of NaOH as

W=m×Mw = 0.05×40=2 grams

Hence we found the required mass of NaOH as 2 grams.

Now talking about shortcut

we know as explained above M=m/V(L) and m=W/M

Substituting value of m(no of moles) in M=m/V(L) we get M=WMw×V(L)

Try substituting the values yourself and get the answer

Note :: The value of Volume should always be substituted in terms of Litre only. That is the reason i used the letter (L) at all the places with V

So thats all get the answer and comment any other problems below

Hope you got your problem solved

Thanks!!!

7 0

3 years ago

The complex [Ni(CN)4]2- is diamagnetic and the complex [NiCl4]2- is paramagnetic. What can you conclude about their molecular ge

quester [9]

Answer:

[Ni(CN)4]2- square planar

[NiCl4]2- tetrahedral

Explanation:

For a four coordinate complex such as [Ni(CN)4]2- and [NiCl4]2-, we can decide its geometry by closely considering its magnetic properties. Both of the complexes are d8 complexes which could be found either in the tetrahedral or square planar crystal field depending on the nature of the ligand.

CN^- being a strong field ligand leads to the formation of a square planar diamagnetic d8 complex of Ni^2+. Similarly, Cl^- being a weak field ligand leads to the formation a a tetrahedral paramagnetic d8 complex of Ni^+ hence the answer given above.

7 0

3 years ago

WILL GiVe bRaInLiEsT, 5 sTaR, AnD tHaNkS!!!!

Nataliya [291]

The answer is more protons than electrons.

5 0

3 years ago

If the energy of photon emitted from the hydrogen atom is 4.09 x 10-19 J, what is

Aliun [14]

Answer:

486 nm

Explanation:

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

Energy (E) = 4.09×10¯¹⁹ J

Wavelength (λ) =?

Next, we shall determine the frequency of the photon. This can be obtained as follow:

Energy (E) = 4.09×10¯¹⁹ J

Planck's constant (h) = 6.63×10¯³⁴ Js

Frequency (f) =?

E = hf

4.09×10¯¹⁹ = 6.63×10¯³⁴ × f

Divide both side by 6.63×10¯³⁴

f = 4.09×10¯¹⁹ / 6.63×10¯³⁴

f = 6.17×10¹⁴ Hz

Next, we shall determine the wavelength of the photon. This can be obtained as follow:

Frequency (f) = 6.17×10¹⁴ Hz

Velocity of photon (v) = 3×10⁸ m/s

Wavelength (λ) =?

v = λf

3×10⁸ = λ × 6.17×10¹⁴

Divide both side by 6.17×10¹⁴

λ = 3×10⁸ / 6.17×10¹⁴

λ = 4.86×10¯⁷ m

Finally, we shall convert 4.86×10¯⁷ m to nm. This can be obtained as follow:

1 m = 1×10⁹ nm

Therefore,

4.86×10¯⁷ m = 4.86×10¯⁷ m × 1×10⁹ nm / 1 m

4.86×10¯⁷ m = 486 nm

Therefore, the wavelength of the photon is 486 nm

7 0

3 years ago

Find the fugacity coefficient of a gaseous species of mole fraction 0.4 and fugacity 25 psia in a mixture at a total pressure of

Oksana_A [137]

<u>Answer:</u> The fugacity coefficient of a gaseous species is 1.25

<u>Explanation:</u>

Fugacity coefficient is defined as the ratio of fugacity and the partial pressure of the gas. It is expressed as $\bar{\phi}$

Mathematically,

$\bar{\phi}_i=\frac{\bar{f_i}}{p_i}$

Partial pressure of the gas is expressed as:

$p_i=\chi_iP$

Putting this expression is above equation, we get:

$\bar{\phi}_i=\frac{\bar{f_i}}{\chi_iP}$

where,

$\bar{\phi}_i$ = fugacity coefficient of the gas

$\bar{f_i}$ = fugacity of the gas = 25 psia

$\chi_i$ = mole fraction of the gas = 0.4

P = total pressure = 50 psia

Putting values in above equation, we get:

$\bar{\phi}_i=\frac{25}{0.4\times 50}\\\\\bar{\phi}_i=1.25$

Hence, the fugacity coefficient of a gaseous species is 1.25

8 0

3 years ago

What kinds of things can we learn by studying atoms?​

What kinds of things can we learn by studying atoms?