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3 years ago

Which of the following represents an ion? a 4he b Na 2+ c Ca d Mg

Chemistry

1 answer:

liubo4ka [24]3 years ago

7 0

Na2+(answer B) represent ions.

<h3>Explanation</h3>

This is because it has a charge of 2+. ion is formed when an atom gain or lose electrons. when an atom lose electrons it form ion which is positively charged . On the other hand when atom gain electrons it forms ion of negatively charged. Na2+ has a charge of 2+ since it loses two electrons.

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3 years ago

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Answer:

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3 years ago

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Answer:

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3 years ago

A chemist prepares a sample of helium gas at a certain pressure, temperature and volume and then removes all but a fourth of the

Stells [14]

Answer:

e. T₂= 4T₁

Explanation:

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P . V = n₁ . R . T₁

where,

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We can rearrange this equation like:

$T_{1}=\frac{P.V}{n_{1}.R}$

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$P.V=n_{2}.R.T_{2}=\frac{1}{4} n_{1}.R.T_{2}\\\frac{P.V}{n_{1}.R} =\frac{1}{4} T_{2}\\T_{1}=\frac{1}{4} T_{2}\\T_{2}=4.T_{1}$

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3 years ago

C3H8+3O2 = 3CO2+4H2O what is the enthalpy combustion

dezoksy [38]

Answer:

$\Delta H_{comb}=2043.85kJ/mol$

Explanation:

Hello there!

In this case, according to the given chemical reaction, it possible for us to set up the expression for the calculation of the enthalpy change as shown below:

$\Delta H_r=-\Delta H_{comb}=3\Delta _fH_{CO_2}+4\Delta _fH_{H_2O}-\Delta _fH_{C_3H_8}-3\Delta _fH_{O_2}$

Thus, given the values of the enthalpies of formation on the attached file, we obtain: $-\Delta H_{comb}=3(-393.5kJ/mol)+4(-241.8kJ/mol)-(-103.85kJ/mol)-3(0kJ/mol)\\\\-\Delta H_{comb}=-2043.85kJ/mol\\\\\Delta H_{comb}=2043.85kJ/mol$

Best regards!

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3 years ago