All categories

3 years ago

How to do this question plz answer

Chemistry

1 answer:

Ira Lisetskai [31]3 years ago

6 0

Explanation:

This is a pretty simple question of mole concept and the solution goes like this:

Given:

Volume of NaOH = 500 mL

Molarity of the aqueous solution = 0.5 M

Molar mass of NaOH= (23+16+1)g = 40g

Let the mass of NaOH be x.

Now , according to formula number of moles of a given substance = given mass/molar mass

Therefore, no. Of moles of NaOH= x/40

Since, molarity = number of moles of solute/ volume of solution in lit.

Hence, 0.5 = (x/40)/(500/1000)

Solving this we get x= 10g

Hence, 10g of NaOH should be taken to obtain a 0.5 M solution of volume 500 mL.

I hope I could explain the numerical well and help you.

You might be interested in

What is the pH of a 0.083 solution of HCI

quester [9]

Answer:

The pH is 1.08, being an acid pH

Explanation:

pH is a parameter used to measure the degree of acidity or alkalinity of a substance. The pH scale ranges from 0 to 14. Values less than 7 indicate the acidity range and those greater than 7 indicate alkalinity or basicity. Value 7 is considered neutral. Mathematically, pH is the negative logarithm of the molar concentration of hydrogen or proton ions (H⁺) or hydronium ions (H₃O⁺).

pH= - log [H⁺]= - log [H₃O⁺]

A strong acid is an acid that completely dissociates into hydrogen ions and anions in solution. This implies that the initial concentration of acid is equal to the final concentration of H₃O⁺. This occurs with acid HCl.

So, pH is calculated as:

pH= - log (0.083)

pH= 1.08

The pH is 1.08, being an acid pH

8 0

3 years ago

10 What is a characteristic of all living organisms?

Vladimir [108]

Answer:

D - ingestion

Explanation:

7 0

2 years ago

Read 2 more answers

In which of these diatomic molecules would you NOT find an octet of electrons

Semmy [17]

Answer:

The hydrogen molecule is the only one in which can not find an octet of electrons around each atom.

Explanation:

Let's evaluate each case.

1. Nitrogen (N₂):

With Z = 7, nitrogen has the following electronic configuration

1s²

2s² 2p³ → valence electrons

Since its valence electrons are 5, in the molecule one nitrogen atom shares 3 electrons with the other one, and each remains with an electron pair, so each atom has an octet of electrons.

2. Hydrogen (H₂):

With Z = 1, its electronic configuration is:

1s¹ → valence electron

In the molecule, the hydrogen atoms share the only electron they have, so they will have only 2 electrons around. In this diatomic molecule, we can not find an octet.

3. Oxygen (O₂):

Z = 8. Electronic configuration:

1s²

2s² 2p⁴ → valence electrons

In the diatomic molecule, each oxygen atom shares 2 electrons with the other one and remains with 2 pairs of electrons, therefore, each oxygen atom has an octet.

4. Fluorine (F₂)

Z = 9. Electronic configuration:

1s²

2s² 2p⁵ → valence electrons

In this molecule, each fluorine atom shares 1 electron with the other and remains with 3 pairs of electrons, hence, each fluorine atom has an octet of electrons around.

Finally, we can say that the hydrogen molecule is the only one in which can not find an octet of electrons around each atom.

I hope it helps you!

8 0

2 years ago

Place the following covalent bonds in order from least to most polar: a. H-Cl b. H-Br c. H-S d. H-C

timofeeve [1]

Answer:

The Order is as follow,

C-H < S-H < H-Br < H-Cl

Explanation:

Polarity depends on the electronegativity difference between two atoms, greater the electronegativity difference, greater will be the polarity of bond and vice versa.

Electronegativity Difference between Hydrogen and other given elements are as follow,

1) C-H;

E.N of Carbon = 2.55

E.N of Hydrogen = 2.20

------------

Difference 0.35

2) S-H;

E.N of Sulfur = 2.58

E.N of Hydrogen = 2.20

------------

Difference 0.38

3) H-Br;

E.N of Bromine = 2.96

E.N of Hydrogen = 2.20

-------------

Difference 0.76

4) H-Cl;

E.N of Chlorine = 3.16

E.N of Hydrogen = 2.20

-----------

Difference 0.96

Hence it is proved that the greatest electronegativity difference is found between H and Chlorine in H-Cl, therefore it is highly polar bond and vice versa.

7 0

3 years ago

A 15.00 % by mass solution of lactose (C 12H 22O 11, 342.30 g/mol) in water has a density of 1.0602 g/mL at 20°C. What is the mo

Alik [6]

Answer:

22.82M

Explanation:

342.3g/mol is présent in 1000

what about in 15??

( 342.3g/mol × 1000 ) ÷ 15

3 0

2 years ago