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3 years ago

6

Modern masonry fireplaces are based on designs first developed _____.

1 answer:

bazaltina [42]3 years ago

3 0

A during the little ice age

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Which of the following popular sayings is an example of a true scientific theory?

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In the molecule NO2 which element is pulling the electrons

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4 years ago

250 mL of a salt solution with a concentration of 15.0 g/L is mixed with 220 mL of a salt solution containing 6.0% salt (m/v).

vlabodo [156]

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3 years ago

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What coefficients would balance the following equation?<br><br> __C2H6 + __O2 → __CO2 + __H2O

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3 years ago

En la electrólisis del Cloruro de plomo se han depositado 2.6 gramos del metal en 20 minutos el peso atómico del plomo es 206 ca

mart [117]

Answer:

2.01 A

Explanation:

Para esta pregunta debemos empezar por la semi-reaccion del plomo:

$Pb^+^2~_(_a_q_)~+~2e^-~->~Pb_(_s_)$

Se intercambian dos electrones en la semi-reacción del plomo. Si tenemos en cuenta la ecuación:

$n=\frac{I*t}{z*F}$

Donde:

<u>n= Moles depositados </u>

<u>I= Intensidad de corriente (en Amperios)</u>

<u>z= Numero de electrones intercambiados</u>

<u>F= Constante de faraday = 96484 C/mol</u>

<u>t=tiempo (en segundos)</u>

Que conocemos de esta ecuación?

<u>Los moles (se pueden calcular a partir de la masa atómica del plomo, 207.2 g/mol)</u>

$2.6~g~Pb\frac{1~mol~Pb}{207.2~g~Pb}=0.0125~mol~Pb$

<u>El tiempo (hay que convertirlo a segundos):</u>

$20~min\frac{60~s}{1~min}=1200~s$

<u>Z (Numero de electrones)</u>

De acuerdo a la semi-reacción son intercambiados 2 electrones.

<u>Por lo tanto podemos resolver para "I":</u>

$I=\frac{n*z*F}{t}=\frac{0.0125~mol*2*96484\frac{C}{mol}}{1200~s}$

$I~=~2.01~\frac{C}{s}=2.01~A$

Espero que sea de ayuda!

6 0

3 years ago