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3 years ago

How many moles of sodium are in a sample of 46g?

1 answer:

3 0

Molar mass Na = 22.98 g/mol

Therefore:

1 mole Na ----------- 22.98 g
? moles Na ---------- 46 g

46 x 1 / 22.98 => 2.001 moles of Na

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If adequate o2 is present in the mitochondria, pyruvic acid will be converted to ______; if conditions are anaerobic, pyruvic ac

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Presence of Oxygen in mitochondria is called Aerobic conditions and under this aerobic conditions Pyruvic acid is converted into Acetyl Co.A which enters Krebs' cycle
while in absence of oxygen which called Anaerobic conditions pyruvic acid is converted into Lactic acid to avoid accumulation of NADH⁺ which inhibit glycolysis and provide NAD⁺ required for glycolysis
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3 years ago

Which of these are true for the reaction above?

agasfer [191]

Answer:

a, d, f

Explanation:

ΔHrxn = ΔH(CCl4) -ΔH(CH4) = - 106.7 -(-74.8) = - 31.9 kJ/mol

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4 years ago

A dangerous condition such that contact or equipment failure can result in. electric shock, arc-flash burn, thermal burn, or bla

Deffense [45]

<h3>Answer:</h3>

Electrical Hazard

Hope it helps!!

4 0

2 years ago

Read 2 more answers

solution is 2.41 molal toluene (C 7H 8, 92 g/mol) in benzene (C 6H 6, 78 g/mol); i.e. consider toluene the solute, benzene the s

inn [45]

Answer : The molarity of solution is, 1.73 mole/L

Explanation :

The relation between the molarity, molality and the density of the solution is,

where,

$d=M[\frac{1}{m}+\frac{M_b}{1000}]$

d = density of solution = $0.876g/cm^3=0.876g/mL$

m = molality of solution = 2.41 mol/kg

M = molarity of solution = ?

$M_b$ = molar mass of solute (toluene) = 92 g/mole

Now put all the given values in the above formula, we get the molality of the solution.

$0.876g/ml=M\times [\frac{1}{2.41mol/kg}+\frac{92g/mole}{1000}]$

$M=1.73mol/L$

Therefore, the molarity of solution is, 1.73 mole/L

7 0

3 years ago

Consider the reaction below for which K = 78.2 atm-1. A(g) + B(g) ↔ C(g) Assume that 0.386 mol C(g) is placed in the cylinder re

borishaifa [10]

Answer:

1.65 L

Explanation:

The equation for the reaction is given as:

A + B ⇄ C

where;

numbers of moles = 0.386 mol C (g)

Volume = 7.29 L

Molar concentration of C = $\frac{0.386}{7.29}$

= 0.053 M

A + B ⇄ C

Initial 0 0 0.530

Change +x +x - x

Equilibrium x x (0.0530 - x)

$K = \frac{[C]}{[A][B]}$

where

K is given as ; 78.2 atm-1.

So, we have:

$78.2=\frac{[0.0530-x]}{[x][x]}$

$78.2= \frac{(0.0530-x)}{(x^2)}$

$78.2x^2= 0.0530-x$

$78.2x^2+x-0.0530=0$

Using quadratic formula;

$\frac{-b+/-\sqrt{b^2-4ac} }{2a}$

where; a = 78.2 ; b = 1 ; c= - 0.0530

= $\frac{-b+\sqrt{b^2-4ac} }{2a}$ or $\frac{-b-\sqrt{b^2-4ac} }{2a}$

= $\frac{-(1)+\sqrt{(1)^2-4(78.2)(-0.0530)} }{2(78.2)}$ or $\frac{-(1)-\sqrt{(1)^2-4(78.2)(-0.0530)} }{2(78.2)}$

= 0.0204 or -0.0332

Going by the positive value; we have:

x = 0.0204

[A] = 0.0204

[B] = 0.0204

[C] = 0.0530 - x

= 0.0530 - 0.0204

= 0.0326

Total number of moles at equilibrium = 0.0204 + 0.0204 + 0.0326

= 0.0734

Finally, we can calculate the volume of the cylinder at equilibrium using the ideal gas; PV =nRT

if we make V the subject of the formula; we have:

$V = \frac{nRT}{P}$

where;

P (pressure) = 1 atm

n (number of moles) = 0.0734 mole

R (rate constant) = 0.0821 L-atm/mol-K

T = 273.15 K (fixed constant temperature )

V (volume) = ???

$V=\frac{(0.0734*0.0821*273.15)}{(1.00)}$

V = 1.64604

V ≅ 1.65 L

3 0

3 years ago