The diameter of carbon atom is.000000000154m. What is this expressed in scientific notation.

Determine the amount of water that must be added to a 2-litre solution of sulphuric acid to dilute it from a pH of 2.7 to a pH o

Ksivusya [100]

Answer:

Volume of water added = 2.0 L

Explanation:

Initial pH of the solution = 2.7

[H^+] concentration in 2 L solution of sulfuric acid,

$pH = -log[H^+]$

$[H^+] = 10^{-pH}\ M$

$[H^+] = 10^{-2.7} = 0.001995\ M = 0.002\ M$

Final pH of the solution = 3

Final [H^+] concentration of sulfuric acid,

$[H^+] = 10^{-pH}\ M$

$[H^+] = 10^{-3} = 0.001\ M$

Now,

$M_1V_1=M_2V_2$

$0.002 \times 2.0 = 0.001 \times V_2$

$V_2 = \frac{0.002 \times 2.0}{0.001} = 4.00\ L$

Volume added = Final volume - Initial volume

= 4.0 - 2.0 = 2.0 L

4 0

3 years ago

Write an electron configuration for an atom of aluminum-27 in an excited state

andrew11 [14]

Ground state of Al is 1s²2s²2p⁶3s²3p¹.
Exited state of Al is 1s²2s²2p⁶3s¹3p².

8 0

3 years ago

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URGENT!! Can someone please explain this to me?

djverab [1.8K]

Answer:

$CH _{4}+ 2O _{2} → CO _{2} + 2H _{2}O$

for the balanced equation

$from \: the \: equation \\ 1 \: mole \: of \: methane \: gives \: 1 \: mole \: of \: carbon \: dioxide \\ 7.4 \: moles \: of \: carbon \: dioxide \: will \: be \: given \: by \: (7.4 \times 1)moles \: of \: methane \\ = 7.4\: moles \: of \: methane \\ \\ since \: moles \: of \: oxygen \: double \: those \: of \: methane \\ moles \: of \: oxygen \: = 7.4\times 2 \\ = 14.8 \: moles \: of \: oxygen$

4 0

3 years ago

Toluene (C6H5CH3 ), an organic compound often used as a solvent in paints, is mixed with a similar organic compound, benzene (C6

Sergeeva-Olga [200]

Explanation:

The given data is as follows.

Weight of solute = 75.8 g, Molecular weight of solute (toulene) = 92.13 g/mol, volume = 200 ml

Therefore, molarity of toulene is calculated as follows.

Molarity = $\frac{\text{weight of solute}}{\text{molecular weight of solute}} \times \frac{1000}{\text{volume of solution in ml}}$

= $\frac{75.8 g}{92.13 g/mol} \times \frac{1000}{200 ml}$

= 4.11 M

Hence, molarity of toulene is 4.11 M.

As molality is the number of moles of solute present in kg of solvent.

So, we will calculate the molality of toulene as follows.

Molality = $\frac{\text{given weight of solute}}{\text{given molecular weight of solute}} \times \frac{1000}{\text{weight of solvent in grams}}$

= $\frac{75.8 g}{92.13 g/mol} \times \frac{1000}{95.6 g}$

= 8.6 m

Hence, molality of given toulene solution is 8.6 m.

Now, calculate the number of moles of toulene as follows.

No. of moles = $\frac{mass}{\text{molar mass}}$

= $\frac{75.8 g}{92.13 g/mol}$

= 0.8227 mol

Now, no. of moles of benzene will be as follows.

No. of moles = $\frac{mass}{\text{molar mass}}$

= $\frac{95.6 g}{78.11 g/mol}$

= 1.2239 mol

Hence, the mole fraction of toulene is as follows.

Mole fraction = $\frac{\text{moles of toulene}}{\text{total moles}}$

= $\frac{0.8227 mol}{(0.8227 + 1.2239) mol}$

= 0.402

Hence, mole fraction of toulene is 0.402.

As density of given solution is 0.857 $g/cm^{3}$ so, we will calculate the mass of solution as follows.

Density = $\frac{mass}{volume}$

0.857 $g/cm^{3}$ = $\frac{mass}{200 ml}$ (As 1 $cm^{3}$ = 1 g)

mass = 171.4 g

Therefore, calculate the mass percent of toulene as follows.

Mass % = $\frac{\text{mass of solute}}{\text{mass of solution}} \times 100$

= $\frac{75.8 g}{171.4 g} \times 100$

= 44.22%

Therefore, mass percent of toulene is 44.22%.

8 0

3 years ago

Pls help I’ll mark brainliest pls pls pls

katovenus [111]

The tea was no longer hot or (brewed) so the 5th didn’t dissolve like the others because the tea was hot or warm enough anymore it cooled down. So the sugar won’t dissolve no more.

7 0

3 years ago

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