Answer: el estudio de la síntesis, estructura, reactividad y propiedades del diverso grupo de compuestos químicos construidos principalmente de carbono

Explanation:Hope I helped:)

8 0

3 years ago

When glass is formed, which of these takes place FIRST? A) The sand turns to liquid. B) The molecules become hard. C) The sand i

otez555 [7]

I would say D and if that's not it it's A

Hope This Helps! Have A Nice Day!!

5 0

3 years ago

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) B5H9(l) is a colorless liquid that will explode when exposed to oxygen. How much heat is released when 0.211 mol of B5H9 react

Tom [10]

<u>Answer:</u> The amount of heat released when 0.211 moles of $B_5H_9(l)$ reacts is 554.8 kJ

<u>Explanation:</u>

The chemical equation for the reaction of $B_5H_9$ with oxygen gas follows:

$2B_5H_9(l)+12O_2(g)\rightarrow 5B_2O_3(s)+9H_2O(l)$

The equation for the enthalpy change of the above reaction is:

$\Delta H_{rxn}=[(5\times \Delta H_f_{(B_2O_3(s))})+(9\times \Delta H_f_{(H_2O(l))})]-[(2\times \Delta H_f_{(B_5H_9(l))})+(12\times \Delta H_f_{(O_2(g))})]$

We are given:

$\Delta H_f_{(H_2O(l))}=-285.4kJ/mol\\\Delta H_f_{(B_2O_3(s))}=-1272kJ/mol\\\Delta H_f_{(B_5H_9(l))}=73.2kJ/mol\\\Delta H_f_{(O_2(g))}=0kJ/mol$

Putting values in above equation, we get:

$\Delta H_{rxn}=[(2\times (-1272))+(9\times (-285.4))]-[(2\times (73.2))+(12\times (0))]\\\\\Delta H_{rxn}=-5259kJ$

To calculate the amount of heat released for the given amount of $B_5H_9(l)$ , we use unitary method, we get:

When 2 moles of $B_5H_9(l)$ reacts, the amount of heat released is 5259 kJ

So, when 0.211 moles of $B_5H_9(l)$ will react, the amount of heat released will be = $\frac{5259}{2}\times 0.211=554.8kJ$

Hence, the amount of heat released when 0.211 moles of $B_5H_9(l)$ reacts is 554.8 kJ

7 0

3 years ago

When an ice cube melt a solid is converted to a liquid ​

When an ice cube melt a solid is converted to a liquid