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4 years ago

Which elements are part of the halogens group?

Chemistry

1 answer:

larisa [96]4 years ago

5 0

The correct answer is Cl, Br, and F. They are all in the halogens group.

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Which of the is an example of climate???<br> Help pls?

n200080 [17]

The first one, my friend

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3 years ago

Read 2 more answers

To determine the concentration of ethanol in cognac a 5.00 mL sample of the cognac is diluted to 0.500 L. Analysis of the dilute

julia-pushkina [17]

Answer : The molar concentration of ethanol in the undiluted cognac is 8.44 M

Explanation :

Using neutralization law,

$M_1V_1=M_2V_2$

where,

$M_1$ = molar concentration of undiluted cognac = ?

$M_2$ = molar concentration of diluted cognac = 0.0844 M

$V_1$ = volume of undiluted cognac = 5.00 mL = 0.005 L

$V_2$ = volume of diluted cognac = 0.500 L

Now put all the given values in the above law, we get molar concentration of ethanol in the undiluted cognac.

$M_1\times 0.005L=0.0844M\times 0.500L$

$M_1=8.44M$

Therefore, the molar concentration of ethanol in the undiluted cognac is 8.44 M

4 0

4 years ago

Which elements does sulfate ion contain?

Rom4ik [11]

Answer: Sulphur and Oxygen

Explanation: Sulphate ion is $SO_4^{2-}$ . It is polyatomic ion which is formed by the combination of sulphur and oxygen elements in the ratio of 1:4.

It is negatively charged species and thus is named by the name _ate at the end.

It usually exists with positively charged species to get stable. eg: ferrous sulphate ( $FeSO_4$ )

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3 years ago

A liquid with a high viscosity cannot be a mixture.

enot [183]

It can be made true by changing "cannot" to "can".

5 0

3 years ago

A mysterious white powder could be powdered sugar (C12H22O11), cocaine (C17H21NO4), codeine (C18H21NO3), norfenefrine (C8H11NO2)

konstantin123 [22]

Answer: norfenefrine $(C_8H_{11}NO_2)$

Explanation:

Depression in freezing point is given by:

$\Delta T_f=i\times K_f\times m$

$\Delta T_f=T_f^0-T_f=(-114.6-(-115.5)^0C=0.9^0C$ = Depression in freezing point

i= vant hoff factor = 1 (for non electrolyte)

$K_f$ = freezing point constant = $1.99^0C/m$

m= molality

$\Delta T_f=i\times K_f\times \frac{\text{mass of solute}}{\text{molar mass of solute}}\times \text{weight of solvent in kg}}$

Weight of solvent (ethanol)= $density\times volume=0.789g/cm^3\times 1.50cm^3=1.18g=1.18\times 10^{-3}kg$

Molar mass of unknown non electrolyte = M g/mol

Mass of unknown non electrolyte added = 82 mg = 0.082 g (1g=1000mg)

$0.9=1\times 1.99\times \frac{0.082g}{M g/mol\times 1.18\times 10^{-3}}kg}$

$M=154g/mol$

The molecular mass of norfenefrine $(C_8H_{11}NO_2)$ is near to 154 and thus the identity of the white powder is norfenefrine .

4 0

3 years ago