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3 years ago

Which animal can leave its eggs to hatch and does not need to take care of the infants?

Chemistry

2 answers:

Komok [63]3 years ago

7 0

Sea turtles, penguins hold them in a pouting, ducks keep them around sea turtles leave them

Murljashka [212]3 years ago

4 0

Sea turtles they leave them on the beach

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Based on the information in the tables, what is the Enthalpy of the solution for each substance? Please help me with this proble

3241004551 [841]

Answer: mg(OH)2 = +37

Rbl = 31

RbOH= -83

mgl2= -144

Explanation: just did it on edge2020

5 0

3 years ago

What would cause the percent yield of a reaction to be less than 100%?

Roman55 [17]

Answer:

All of the limiting reagent gets used up causes the percent yield of a reaction to be less than 100%

Explanation:

It is rare for a chemical reaction to occur with the right proportion of reactants that reacts together to form resultant products.During this process, one of the reactants gets used up faster resulting in the lower percent yield. Such product that gets used up faster is called limiting reagent. This limiting reagent is responsible for lowering the percentage yield in the chemical reaction.

The limiting reactant can be found easily by calculating the yield of each reactant assuming they are consumed completely. The reactant which has least yield is the limiting reactant of the reaction.

3 0

3 years ago

Describe light with respect to its speed and its dual nature as both a wave and a particle.

Sedbober [7]

Answer:

Scientists have been debating over light being a wave or particle since its recognition.

Sir Issac Newton discovered that light had frequency and other properties. Newton described light to be a particle because it created shadows which were sharp and very clear.

Francesco Maria Grimaldi, claimed that light was a wave. This was because this scientist observed the diffraction of light and hence, claimed light to be a type of wave.

The speed of light is 299 792 458 m / s. Nothing can travel faster than light.

5 0

3 years ago

Calculate the EMF between copper and silver Ag+e-E=0.89v 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

The radius of a lithium atom is 130 picometers, and the radius of a fluorine atom is 60 picometers. The radius of a lithium ion,

natali 33 [55]

Answer:

A positive ions is always smaller than the corresponding atom.

A negative ion is always larger than the corresponding atom.

Explanation:

The reason for this is that, when a positive ion is formed, a full shell is usually removed with its electrons thereby reducing the size of the electron cloud and decreasing the size of the electron cloud.

A negative ion is formed by addition of more electrons to the electron cloud hence it spreads out. Interelectronic repulsion accounts for the larger size of the negative ion.

3 0

3 years ago