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Vera_Pavlovna [14]

2 years ago

8

A chemist adds 215.0mL of a 6.0x10^−5/mmolL mercury(II) iodide HgI2 solution to a reaction flask. Calculate the micromoles of me

rcury(II) iodide the chemist has added to the flask. Round your answer to 2 significant digits.

1 answer:

Snezhnost [94]2 years ago

6 0

The micromoles of mercury(II) iodide : 0.013 μ moles

<h3>Further explanation</h3>

Given

215.0mL of a 6.0x10⁻⁵mmol/L HgI₂

Required

micromoles of HgI₂

Solution

Molarity(M) = moles of solute per liters of solution

Can be formulated :

M = n : V

n = moles

V = volume of solution

V = 215 mL = 0.215 L

so moles of solution :

n = M x V

n = 6.10 mmol/L x 0.215 L

n = 1.312 . 10⁻⁵ mmol

mmol = 10³ micromol

so 1.312 mmol = 1.312.10⁻⁵ x 10³ = 0.01312 micromoles ⇒ 2 sif fig = 0.013 μ moles

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Answer:

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2 years ago

Under identical conditions, separate samples of O2 and an unknown gas were allowed to effuse through identical membranes simulta

scoray [572]

Answer:

70.77 g/mol is the molar mass of the unknown gas.

Explanation:

Effusion is defined as rate of change of volume with respect to time.

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The rate of diffusion of gas, we use Graham's Law.

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$\text{Rate of effusion}\propto \frac{1}{\sqrt{\text{Molar mass of the gas}}}$

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8 0

3 years ago

Is H3O+ polar or non polar? (explain please.)?

pishuonlain [190]

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2 years ago

a strip of impure copper is given to you. how will you purify it by using chemical effects of electric current ?

Oksi-84 [34.3K]

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When the electric current is switched on, the bar of pure copper which is the cathode increases greatly in size as copper ions leave the anode of impure copper and attach to the cathode. The anode becomes smaller and smaller as it loses copper ions until all that is left of it is impurities in form of a sludge beneath it.

6 0

2 years ago

Read 2 more answers

A critical reaction in the production of energy to do work or drive chemical reactions in biological systems is the hydrolysis o

MAVERICK [17]

Answer : The value of $\Delta G_{rxn}$ is -49.6 kJ/mol

Explanation :

First we have to calculate the reaction quotient.

Reaction quotient (Q) : It is defined as the measurement of the relative amounts of products and reactants present during a reaction at a particular time.

The given balanced chemical reaction is,

$ATP(aq)+H_2O(l)\rightarrow ADP(aq)+HPO_4^{2-}(aq)$

The expression for reaction quotient will be :

$Q=\frac{[ADP][HPO_4^{2-}]}{[ATP]}$

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

Given:

$[ATP]$ = 5.0 mM

$[ADP]$ = 0.60 mM

$[HPO_4^{2-}]$ = 5.0 mM

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

$Q=\frac{(0.60)\times (5.0)}{(5.0)}=0.60mM=0.60\times 10^{-3}M$

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 = -30.5 kJ/mol

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

T = temperature = $37.0^oC=273+37.0=310K$

Q = reaction quotient = $0.60\times 10^{-3}$

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

$\Delta G_{rxn}=(-30.5kJ/mol)+[(8.314\times 10^{-3}kJ/mole.K)\times (310K)\times \ln (0.60\times 10^{-3})$

$\Delta G_{rxn}=-49.6kJ/mol$

Therefore, the value of $\Delta G_{rxn}$ is -49.6 kJ/mol

6 0

2 years ago