All categories

2 years ago

A solution contains 90 milliequivalents of HC1 in 450ml. What is its normality?

Chemistry

1 answer:

Rashid [163]2 years ago

7 0

Answer:

Normality N = 0.2 N

Explanation:

Normality is the number of gram of equivalent of solute divided of volume of solution, where the number of gram of equivalent of solute is weight of the solute divided by the equivalent weight.

Normality is represented by N.

Mathematically, we have :

$\mathbf{Normality \ N = \dfrac{Number \ of \ gram \of \ equivalent\ of\ solute }{volume \ of \ solution}}$

Given that:

number of gram of equivalent of solute = 90 milliequivalents 90 × 10⁻³ equivalent

volume of solution (HCl) = 450 mL 450 × 10⁻³ L

$\mathbf{Normality \ N = \dfrac{90 \times 10^{-3}}{450 \times 10^{-3}}}$

Normality N = 0.2 N

You might be interested in

Describe how you would prepare exactly 100 mL of 0.109 M picolinate buffer, pH 5.61. Possible starting materials are pure picoli

Pepsi [2]

Answer:

1.342g of picolinic acid and 6.743mL of 1.0M NaOH diluting the mixture to 100.0mL

Explanation:

<em>The pKa of the picolinic acid is 5.4.</em>

Using Henderson-Hasselbalch formula for picolinic-picolinate buffer:

pH = pKa + log [Picolinate] / [Picolinic]

<em>Where [] could be taken as moles of each species</em>

<em />

5.61 = 5.4 + log [Picolinate] / [Picolinic]

0.21 = log [Picolinate] / [Picolinic]

1.62181 = [Picolinate] / [Picolinic] <em>(1)</em>

Now, both picolinate and picolinic acid will be:

0.100L * (0.109mol / L) =

0.0109 moles = [Picolinate] + [Picolinic] <em>(2)</em>

First, as we will start with picolinic acid, we need add:

0.0109 moles picolinic acid * (123.10g/mol) = 1.342g of picolinic acid

Now, replacing (2) in (1):

1.62181 = 0.0109 moles - [Picolinic] / [Picolinic]

1.62181 [Picolinic] = 0.0109 moles - [Picolinic]

2.62181 [Picolinic] = 0.0109 moles

[Picolinic] = 4.157x10⁻³ moles

And:

[Picolinate] = 0.0109 - 4.157x10⁻³ moles =

<h3>6.743x10⁻³ moles</h3><h3 />

To obtain these moles of picolinate ion we need to make the reaction of the picolinic acid with NaOH:

Picolinic acid + NaOH → Picolinate + Water

<em>That means to obtain 6.743x10⁻³ moles of picolinate ion we need to add 6.743x10⁻³ moles of NaOH</em>

<em />

6.743x10⁻³ moles of NaOH that is 1.0M are, in mL:

6.743x10⁻³ moles * (1L / 1mol) = 6.743x10⁻³L * 1000 =

<h3>6.743mL of the 1.0M NaOH must be added</h3><h3 />

Thus, we obtain the desire moles of picolinate and picolinic acid to obtain the buffer we want, the last step is:

<h3>Dilute the mixture to 100mL, the volume we need to prepare</h3>

3 0

2 years ago

What could be done to change this carbide ion to a neutral carbon atom? A) remove 2 electrons B) add 2 electrons C) remove 4 ele

bonufazy [111]

Answer:remove 4 electrons

Explanation:

I took the test just a minute a go

5 0

2 years ago

Which of the following is the best piece of laboratory glassware for preparing 500.0 mL of an aqueous solution of a solid?

Leni [432]

Answer:

The correct answer is option A.

Explanation:

Volumetric flask : A glass ware with round lower body with flat bottom and with thin cylindrical neck along with mark which indicates the specific volume filled to that mark.It is used in preparation of standard solution of compound with desired concentration with fixed volume.

Erlenmeyer flask : is a flask with conical shape with flat bottom used in titration experiments to carry out reaction with fixed volume of solution.

Test tube : Small cylindrical tube with rounded bottom used to observe reaction in between reactant taken in small amount.

Graduated beaker : Laboratory glassware used measure larger volumes of solution or to mix or stir solutions and liquids.

Graduated cylinder : Laboratory thin cylindrical glassware with accurate marking of volume used to measure an accurate volume of solutions or liquids required in an experiment.

<em><u>Volumetric flask</u></em> is the best piece of laboratory glassware for preparing 500.0 mL of an aqueous solution of a solid

8 0

2 years ago

Read 2 more answers

HBrO (aq) + H2O (l) ⇋ H3O+ (aq) + BrO- (aq)

joja [24]

Answer:

6.24 x 10-3 M

Explanation:

Hello,

In this case, for the given dissociation, we have the following equilibrium expression in terms of the law of mass action:

$Ka=\frac{[H_3O^+][BrO^-]}{[HBrO]}$

Of course, water is excluded as it is liquid and the concentration of aqueous species should be considered only. In such a way, in terms of the change $x$ , we rewrite the expression considering an ICE table and the initial concentration of HBrO that is 0.749 M:

$5.2x10^{-5}=\frac{x*x}{0.749-x}$

Thus, we obtain a quadratic equation whose solution is:

$x_1=-0.00627M\\x_2=0.00624M$

Clearly, the solution is 0.00624 M as no negative concentrations are allowed, so the concentration of BrO⁻ is 6.24 x 10-3 M.

Best regards.

4 0

2 years ago

Read 2 more answers

____are both centrally located in an atom's nucleus, while ______ electrons surround the nucleus in designated shells (which are

masya89 [10]

<span>Protons and neutrons are both centrally located in an atom's nucleus, while negative electrons surround the nucleus in designated shells (which are commonly thought of as "orbits" as labeled in the PhET simulation).
Nucleus of an atom has positive charge, electrons are negative and atom has neutral net charge.</span>

4 0

2 years ago

Read 2 more answers