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3 years ago

How many moles of NaCl are present in 2.50 L of a 0.070 M solution?

Chemistry

1 answer:

posledela3 years ago

6 0

Given :

Volume of NaCl solution 2.5 L .

Molarity of NaCl solution is 0.070 M .

To Find :

How many moles are present in the solution.

Solution :

Let, n be the number of moles.

We know, molarity is given by :

$M = \dfrac{n}{V(in\ L)}$

So,

$n = M \times V\\\\n = 0.070\times 2.5 \\\\n = 0.175\ moles$

Therefore, number of moles of NaCl is 0.175 moles.

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Camphor is a ketone compound and is one of the active ingredients in vicks products. if camphor has m+ = 152 and contains 1 doub

nordsb [41]

Answer:

C₁₀H₁₆O

Explanation:

Molecular formula can be determined from parent peak by using rule of thirteen.

Rule of Thirteen:

First divide the parent peak value by 13 as,

= 152 ÷ 13

= 11.69

Now, multiply 13 by 11,

= 13 × 11 (here, 11 specifies number of carbon atoms)

= 143

Now subtract 143 from 152,

= 152 - 143

= 9

Add 9 into 11,

= 9 + 11

= 20 (hydrogen atoms)

So, the rough formula we have is,

C₁₁H₂₀

Now, add one Oxygen atom to above formula and subtract one Carbon and 4 Hydrogen atoms as these numbers are equal to atomic mass of Oxygen atom as,

C₁₁H₂₀ -------O--------> C₁₀H₁₆O

Calculate Hydrogen deficiency index as,

HDI = (2x + 2 - y) / 2

where,

x = C atoms

y = H atoms

HDI = [2(10) + 2 - 16] / 2

HDI = (20 + 2 - 16) / 2

HDI = (22-16) / 2

HDI = 6 / 2

HDI = 3

It means, Camphor contains 1 double bond and two rings. As, HDI of double bond is 1 and HDI of one ring is 1.

7 0

4 years ago

Which chemistry studies non carbon based structures?

Tasya [4]

Answer:

Inorganic chemistry

Explanation:

Meaning: Inorganic chemistry studies substances that do not contain carbon; therefore, it studies non carbon based structure.

8 0

3 years ago

For IR radiation with û = 1,130 cm 1, v=__THz

Dmitry [639]

Answer: The frequency of the radiation is 33.9 THz

Explanation:

We are given:

Wave number of the radiation, $\bar{\nu}=1130cm^{-1}$

Wave number is defined as the number of wavelengths per unit length.

Mathematically,

$\bar{\nu}=\frac{1}{\lambda}$

where,

$\bar{\nu}$ = wave number = $1130cm^{-1}$

$\lambda$ = wavelength of the radiation = ?

Putting values in above equation, we get:

$1130cm^{-1}=\farc{1}{\lambda}\\\\\lambda=\frac{1}{1130cm^{-1}}=8.850\times 10^{-4}cm$

Converting this into meters, we use the conversion factor:

1 m = 100 cm

So, $8.850\times 10^{-4}cm=8.850\times 10^{-4}\times 10^{-2}=8.850\times 10^{-6}m$

The relation between frequency and wavelength is given as:

$\nu=\frac{c}{\lambda}$

where,

c = the speed of light = $3\times 10^8m/s$

$\nu$ = frequency of the radiation = ?

Putting values in above equation, we get:

$\nu=\frac{3\times 10^8m/s}{8.850\times 10^{-4}m}$

$\nu=0.339\times 10^{14}Hz$

Converting this into tera Hertz, we use the conversion factor:

$1THz=1\times 10^{12}Hz$

So, $0.339\times 10^{14}Hz\times \frac{1THz}{1\times 10^{12}Hz}=33.9THz$

Hence, the frequency of the radiation is 33.9 THz

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3 years ago

Environmental studies usually involve an analysis of precipitation and its response to pollution. To quantify the degree of cont

LuckyWell [14K]

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The lake water is acidic.

Explanation:

Data given:

molarity of base solution Mbase = 0.1 M

volume of the base solution Vbase = 0.1 ml or 0.0001 litre

volume of lake water Vlake = 1000ml or 1 litre

molarity of the lake water, Mlake = ?

Using the formula for titration:

Mbase X Vbase = Mlake X

Mlake = $\frac{Mbase X Vbase }{Vlake}$

Putting the values in the equation:

Mlake = $\frac{0.0001 X 0.1}{1}$

Mlake = 0.00001 M

The pH of the lake water will be calculated by using the following formula:

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

pH = - $log_{10}$ [ 0.00001]

pH = 5

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3 years ago

Graph of the relationship between mass and thermal energy

elixir [45]

Thermal energy is the sum of the kinetic and potential energies of all the particles in an object.

Assume that you have 250 gL of water and 1 kg of water at the same temperature.

Then, each water molecule has the same kinetic energy.

The larger sample contains four times as many molecules, so it contains four times as much thermal energy.

Thus, thermal energy is directly proportional to mass.

In symbols, KE ∝ m or KE = km.

The graph of a direct proportion is a straight line passing trough the origin.

It should look something like the graph below.

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4 years ago