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3 years ago

How is the moderm periodic table arranged?

Chemistry

1 answer:

ankoles [38]3 years ago

8 0

Answer:

Explanation:

the elements are arranged according to their atomic number - not their relative atomic mass . In the periodic table the elements are arranged into: rows, called periods , in order of increasing atomic number. vertical columns, called groups , where the elements have similar properties

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Calculate ΔGrxn at 298 K under the conditions shown below for the following reaction.

algol13

Answer : The value of $\Delta G_{rxn}$ is -24.9 kJ/mol

Explanation :

First we have to calculate the value of 'Q'.

The given balanced chemical reaction is,

$Fe_2O_3(s)+3CO(g)\rightarrow 2Fe(s)+3CO_2(g)$

The expression for reaction quotient will be :

$Q=\frac{(p_{CO_2})^3}{(p_{CO})^3}$

In this expression, only gaseous or aqueous states are includes and pure liquid or solid states are omitted.

Now put all the given values in this expression, we get

$Q=\frac{(2.1)^3}{(1.4)^2}$

$Q=3.375$

Now we have to calculate the value of $\Delta G_{rxn}$ .

The formula used for $\Delta G_{rxn}$ is:

$\Delta G_{rxn}=\Delta G^o+RT\ln Q$ ............(1)

where,

$\Delta G_{rxn}$ = Gibbs free energy for the reaction = ?

$\Delta G_^o$ = standard Gibbs free energy = -28.0 kJ/mol

R = gas constant = $8.314\times 10^{-3}kJ/mole.K$

T = temperature = 298 K

Q = reaction quotient = 3.375

Now put all the given values in the above formula 1, we get:

$\Delta G_{rxn}=(-28.0kJ/mol)+[(8.314\times 10^{-3}kJ/mole.K)\times (298K)\times \ln (3.375)$

$\Delta G_{rxn}=-24.9kJ/mol$

Therefore, the value of $\Delta G_{rxn}$ is -24.9 kJ/mol

5 0

3 years ago

On a given day, the water vapor in the air is 2.5%. If the partial pressure of the vapor is 19.4 mm Hg, what is the atmospheric

erica [24]

Answer:775 mm Hg

Explanation:

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3 years ago

Draw the structure of two alkenes that would yield 1-methylcyclohexanol when treated with Hg(OAc)2 in water, then NaBH4:Draw the

disa [49]

Answer:

Two possible compounds are shown below- one with an exocyclic double bond and another one with an endocyclic double bond

Explanation:

Reaction of alkene with $Hg(OAc)_{2}$ gives a complex of mercurous ion.

Then water molecule attacks this complex through $S_{N}2$ type reaction at more substituted position.

$NaBH_{4}$ cleaves the resultant C-Hg bond and forms a C-H bond.

Two possible structures of an alkene is possible to yield 1-methylcyclohexanol which are shown below.

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4 years ago

Between room temperature and its melting point (1132C), pure U metal exists in three crystal phases: alpha, beta, and gamma. Tra

kifflom [539]

Where’s the question at ??..

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3 years ago

Calculate the pH of a solution of 0.0050M H2SO4.

Mice21 [21]

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3 years ago