What do a mole of magnesium and a mole of iron have in common

Explain why lunar eclipses occur during a full moom

n200080 [17]

The answer to you're question is:

~A. Lunar eclipse occurs when the Moon passes directly behind Earth and into its shadow. This can occur only when the Sun, Earth, and Moon are exactly or very closely aligned with Earth between the other two. A lunar eclipse can occur only on the night of a full moon.

Hope this helps!!!

5 0

3 years ago

Calculate the EMF between copper and silver Ag+e-E=0.89v<br>Cu=E=0.34v

bogdanovich [222]

Answer:

Depending on the $E^\circ$ value of $\rm Ag^{+} + e^{-} \to Ag\; (s)$ , the cell potential would be:

$0.55\; \rm V$ , using data from this particular question; or
approximately $0.46\; \rm V$ , using data from the CRC handbooks.

Explanation:

In this galvanic cell, the following two reactions are going on:

The conversion between $\rm Ag\; (s)$ and $\rm Ag^{+}$ ions, $\rm Ag^{+} + e^{-} \rightleftharpoons Ag\; (s)$ , and
The conversion between $\rm Cu\; (s)$ and $\rm Cu^{2+}$ ions, $\rm Cu^{2+}\; (aq) + 2\, e^{-} \rightleftharpoons \rm Cu\; (s)$ .

Note that the standard reduction potential of $\rm Ag^{+}$ ions to $\rm Ag\; (s)$ is higher than that of $\rm Cu^{2+}$ ions to $\rm Cu\; (s)$ . Alternatively, consider the fact that in the metal activity series, copper is more reactive than silver. Either way, the reaction is this cell will be spontaneous (and will generate a positive EMF) only if $\rm Ag^{+}$ ions are reduced while $\rm Cu\; (s)$ is oxidized.

Therefore:

The reduction reaction at the cathode will be: $\rm Ag^{+} + e^{-} \to Ag\; (s)$ . The standard cell potential of this reaction (according to this question) is $E(\text{cathode}) = 0.89\; \rm V$ . According to the 2012 CRC handbook, that value will be approximately $0.79\; \rm V$ .

The oxidation at the anode will be: $\rm Cu\; (s) \to \rm Cu^{2+} + 2\, e^{-}$ . According to this question, this reaction in the opposite direction ( $\rm Cu^{2+}\; (aq) + 2\, e^{-} \rightleftharpoons \rm Cu\; (s)$ ) has an electrode potential of $0.34\; \rm V$ . When that reaction is inverted, the electrode potential will also be inverted. Therefore, $E(\text{anode}) = -0.34\; \rm V$ .

The cell potential is the sum of the electrode potentials at the cathode and at the anode:

$\begin{aligned}E(\text{cell}) &= E(\text{cathode}) + E(\text{anode}) \\ &= 0.89 \; \rm V + (-0.34\; \rm V) = 0.55\; \rm V\end{aligned}$ .

Using data from the 1985 and 2012 CRC Handbook:

$\begin{aligned}E(\text{cell}) &= E(\text{cathode}) + E(\text{anode}) \\ &\approx 0.7996 \; \rm V + (-0.337\; \rm V) \approx 0.46\; \rm V\end{aligned}$ .

5 0

3 years ago

For the reaction 2 HCl + Na2CO3 → 2 NaCl + H2O + CO2 8.0 moles of CO2 is collected at STP. What is the volume of CO2? 1. 57.6 L

Dmitry [639]

Answer:

Option 5. 179L

Explanation:

The reaction is:

2 HCl + Na₂CO₃ → 2NaCl + H₂O + CO₂

The amount of collected CO₂ is 8 moles.

We apply the Ideal Gases Law at STP

STP are 1 atm of pressure and 273K of T°

P . V = n . R . T

1atm . V = 8 mol .0.082L.atm/mol.K . 273K

V = (8 mol .0.082L.atm/mol.K . 273K) / 1 atm = 179 L

6 0

3 years ago

What are the 6 elements of wether

Citrus2011 [14]

The six basic elements of weather include temperature, humidity, atmospheric pressure, wind, precipitation, and cloudiness.

~I knew this was asked 5 days ago, but I hope this still helps.

8 0

3 years ago

HEY I NEED ALL ANSWERS RIGHT NOW IT'S MISSING AND MY TEACHER ARE GRADING THEM NOW YOU WILL BE MARKED BRAINIEST

emmainna [20.7K]

Molar mass of butane:-

4(12)+10=58u

Moles of Butane:-

100/58=1.7mol

#16

2mols of Butane produce 8mol CO_2
1mol of butane produces 4mol CO_2

Moles of CO_2

4(1.7)=6.8mol

Mass of CO_2:-

44(6.8)=299.2g

#17

2mols of butane need 13mol O_2
1mol of butane needs 6.5mol O_2

Moles of O_2

6.5(1.7)=11.05mol

Mass of O_2

11.05(32)=353.6g

7 0

2 years ago