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3 years ago

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Calculate the molar mass of each of the following:

1 answer:

Allushta [10]3 years ago

6 0

Explanation:

Molar mass

The mass present in one mole of a specific species .

The molar mass of a compound , can easily be calculated as the sum of the all the individual atom multiplied by the number of total atoms .

(a) S₈

Molar mass of of the atoms are -

sulfur, S = 32 g/mol.

Molar mass of S₈ = 8 * 32 g/mol. = 256 g/mol.

(b) C₂H₁₂

Molar mass of of the atoms are -

Hydrogen , H = 1 g/mol

Carbon , C = 12 g/mol

Molar mass of C₂H₁₂ = ( 2 * 12 ) + (12 * 1 ) = 36 g /mol

(c) Sc₂(SO₄)₃

Molar mass of of the atoms are -

sulfur, S = 32 g/mol.

oxygen , O = 16 g/mol.

scandium , Sc = 45 g/mol.

Molar mass of Sc₂(SO₄)₃ = (2 * 45 ) + ( 3 *32 ) + ( 12 * 16 ) = 378 g /mol

(d) CH₃COCH₃ (acetone)

Molar mass of of the atoms are -

Carbon , C = 12 g/mol

oxygen , O = 16 g/mol.

Hydrogen , H = 1 g/mol

Molar mass of CH₃COCH₃ (acetone) = (3 * 12 ) + ( 1 * 16 ) + ( 6 * 1 ) = 58g/mol

(e) C₆H₁₂O₆ (glucose)

Molar mass of of the atoms are -

Carbon , C = 12 g/mol

oxygen , O = 16 g/mol.

Hydrogen , H = 1 g/mol

Molar mass of C₆H₁₂O₆ (glucose) = ( 6 * 12 ) + ( 12 * 1 ) + ( 6 * 16 ) = 108g/mol.

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Find the number of moles of water that can be formed if you have 126 mol of hydrogen gas and 58 mol of oxygen gas.

Elden [556K]

Since a water molecule is H2O, you would divide 126 hydrogen molecules by 2, and you would get 63. That means you have 63 double hydrogen molecules, and 58 oxygen molecules to pair up with them. So that means you could have 58 molecules of water, with 5 double hydrogen molecules, so basically 10 extra molecules of hydrogen along with the H2O molecules. Hope I helped! :)

6 0

3 years ago

Read 2 more answers

What is the osmotic pressure of a solution made from 22.3 g of methanol (MM = 32.04 g/mol) that was added to water to make 321 m

xxMikexx [17]

Answer: The osmotic pressure of a solution is 53.05 atm

Explanation:

To calculate the concentration of solute, we use the equation for osmotic pressure, which is:

$\pi=iMRT$

Or,

$\pi=i\times \frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in mL)}}\times RT$

where,

$\pi$ = osmotic pressure of the solution = ?

i = Van't hoff factor = 1 (for non-electrolytes)

Mass of solute (methanol) = 22.3 g

Volume of solution = 321 mL

R = Gas constant = $0.0821\text{ L.atm }mol^{-1}K^{-1}$

T = temperature of the solution = $25^oC=[273+25]=298K$

Putting values in above equation, we get:

$\pi=1\times \frac{22.3\times 1000}{32.04\times 321}\times 0.0821\text{ L.atm }mol^{-1}K^{-1}\times 298K$

$\pi=53.05atm$

Hence, the osmotic pressure of a solution is 53.05 atm

7 0

3 years ago

2-phosphoglycerate(2PG) is converted to phosphoenolpyruvate (PEP) by the enzyme enolase. The standard free energy change(deltaGo

pogonyaev

Answer:

The correct option is: (D) -2.4 kJ/mol

Explanation:

<u>Chemical reaction involved</u>: 2PG ↔ PEP

Given: The standard Gibb's free energy change: ΔG° = +1.7 kJ/mol

Temperature: T = 37° C = 37 + 273.15 = 310.15 K (∵ 0°C = 273.15K)

Gas constant: R = 8.314 J/(K·mol) = 8.314 × 10⁻³ kJ/(K·mol) (∵ 1 kJ = 1000 J)

Reactant concentration: 2PG = 0.5 mM

Product concentration: PEP = 0.1 mM

Reaction quotient: $Q_{r} =\frac{\left [ PEP \right ]}{\left [ 2PG \right ]} = \frac{0.1 mM}{0.5 mM} = 0.2$

<u>To find out the Gibb's free energy change at 37° C (310.15 K), we use the equation:</u>

$\Delta G = \Delta G^{\circ } + 2.303 R T log Q_{r}$

$\Delta G = 1.7 kJ/mol + [2.303 \times (8.314 \times 10^{-3} kJ/(K.mol))\times (310.15 K)] log (0.2)$

$\Delta G = 1.7 + [5.938] \times (-0.699) = 1.7 - 4.15 = (-2.45 kJ/mol)$

<u>Therefore, the Gibb's free energy change at 37° C (310.15 K): </u><u>ΔG = (-2.45 kJ/mol)</u>

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3 years ago

Green plants absorbs sunlight to power photosynthesis, the chemical synthesis of food from water and carbon dioxide. The compoun

Serggg [28]

Answer: The frequency of this light is $6.62\times 10^{14}s^{-1}$

Explanation:

To calculate the wavelength of light, we use the equation:

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

where,

$\lambda$ = wavelength of the light = $453nm=453\times 10^{-9}m$

c = speed of light = $3.0\times 10^8m/s$

$\nu$ = frequency of light = ?

$\nu=\frac{3.0\times 10^8m/s}{453\times 10^{-9}m}=6.62\times 10^{14}s^{-1}$

The frequency of this light is $6.62\times 10^{14}s^{-1}$

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3 years ago

At a given temperature, the elementary reaction A − ⇀ ↽ − B , A↽−−⇀B, in the forward direction, is first order in A A with a rat

Svetllana [295]

Answer:

The equilibrium constant for the reversible reaction = 0.0164

Explanation:

At equilibrium the rate of forward reaction is equal to the rate of backwards reaction.

The reaction is given as

A ⇌ B

Rate of forward reaction is first order in [A] and the rate of backward reaction is also first order in [B]

The rate of forward reaction = |r₁| = k₁ [A]

The rate of backward reaction = |r₂| = k₂ [B]

(Taking only the magnitudes)

where k₁ and k₂ are the forward and backward rate constants respectively.

k₁ = 0.010 s⁻¹

k₂ = 0.0610 s⁻¹

|r₁| = 0.010 [A]

|r₂| = 0.016 [B]

At equilibrium, the rate of forward and backward reactions are equal

|r₁| = |r₂|

k₁ [A] = k₂ [B] (eqn 1)

Note that equilibrium constant, K, is given as

K = [B]/[A]

So, from eqn 1

k₁ [A] = k₂ [B]

[B]/[A] = (k₁/k₂) = (0.01/0.0610) = 0.0163934426 = 0.0164

K = [B]/[A] = (k₁/k₂) = 0.0164

Hope this Helps!!!

5 0

3 years ago