What’s at the end of the leg bones?

4. Quando se obtém a potência máxima da célula, o valor indicado no amperímetro, na unidade SI, está no intervalo: (A) [3,1; 3,2

Annette [7]

Answer:i dont speak english

Explanation:

sorry

8 0

2 years ago

g The reaction; 4 Ag(s) + O2(g) ----> 2 Ag2O(s), is exothermic. Which statement about the reaction is correct? (A) It is spon

melomori [17]

Answer:

The correct answer is B. It is spontaneous only at low temperatures.

Explanation:

In thermodynamics, the Gibbs free energy is a thermodynamic potential that can be used to calculate the maximum of reversible work that may be performed by a thermodynamic system at a constant temperature and pressure.

The spontaneity of a reaction is given by the equation:

ΔG = ΔH - TΔS

where:

ΔH: enthalpy variation

T: absolute temperature

ΔS: entropy variation

As the reaction is exothermic, ΔH<0

As the reaction order increases (the reagents are solid and gas and their product is solid), ΔS<0

Therefore, the reaction will be spontaneous when ΔG is negative.

ΔG = ΔH - TΔS

That is, the entropy term must be smaller than the enthalpy term.

Hence, the reaction will be spontaneous only at low temperatures.

4 0

2 years ago

3. A student carries out the clay-catalyzed dehydration of cyclohexanol starting with 10 moles of cyclohexanol and obtains 500 m

IrinaK [193]

Answer:

$49.45~%$

Explanation:

In this case, we have to start with the chemical reaction:

$C_6H_1_2O~->~C_6H_1_0~+~H_2O$

So, if we start with 10 mol of cyclohexanol ( $C_6H_1_2O$ ) we will obtain 10 mol of cyclohexanol ( $C_6H_1_0$ ). So, we can calculate the grams of cyclohexanol if we calculate the molar mass:

$(6*12)+(10*1)=82~g/mol$

With this value we can calculate the grams:

$10~mol~C_6H_1_0\frac{82~g~C_6H_1_0}{1~mol~C_6H_1_0}=820~g~C_6H_1_0$

Now, we have as a product 500 mL of $C_6H_1_0$ . If we use the density value (0.811 g/mL). We can calculate the grams of product:

$500~mL\frac{0.811~g}{1~mL}=405.5~g$

Finally, with these values we can calculate the yield:

$%~=~\frac{405.5}{820}x100~=~49.45%$ %= (405.5/820)*100 = 49.45 %

See figure 1

I hope it helps!

6 0

3 years ago

A chemical reaction was used to separate a sample into its components. What conclusion about the sample can be formed based on t

frez [133]

It is A I took a test just like this yesterday.

3 0

3 years ago

Read 2 more answers

What is Y? 222/86 Rn A/z + 4/2He

kondaur [170]

$^{222}_{\phantom{2}86}\text{Rn} \to ^{218}_{\phantom{2}84}\text{Po}+ ^{4}_{2}\text{He}$

Y is Po-218.

A = 218
Z = 84.

<h3>Explanation </h3>

$^{222}_{\phantom{2}86}\text{Rn} \to ^{A}_{Z}\text{Y}+ ^{4}_{2}\text{He}$

Here's the symbol of a particle in a nuclear reaction. $^{A}_{Z}\text{Y}$ .

A stands for mass number. Z stands for atomic number. Both numbers shall conserve in a nuclear reaction.

The mass number on the left hand side is 222.
The two mass numbers on the right hand side add up to A + 4.
222 = A + 4.
A = 218

So is the case for the atomic number. Try figure out the atomic number of Y using the same approach.

The atomic number on the left hand side is 86.
The two atomic number on the right hand side add up to __ + __.
86 = __ + __.
Z = 84.

What element is Y? The atomic number of Y is 84. Refer to a periodic table. Element 84 corresponds to Po (polonium). Y is Polonium-218. The symbol of Y should be written as $^{218}_{\phantom{2}84}\text{Po}$ . Hence the equation:

$^{222}_{\phantom{2}86}\text{Rn} \to ^{218}_{\phantom{2}84}\text{Po}+ ^{4}_{2}\text{He}$ .

3 0

2 years ago