All categories

1 year ago

You need to prepare 500 mL of a 0.250 M NaOH solution for a titration. What mass of NaOH is needed to

Chemistry

1 answer:

VikaD [51]1 year ago

5 0

The mass of NaOH needed to prepare the solution is 5 g

<h3>What is molarity? </h3>

This is defined as the mole of solute per unit litre of solution. Mathematically, it can be expressed as:

Molarity = mole / Volume

<h3>How to determine the mole of sodium hydroxide, NaOH</h3>

We'll begin by calculating the moles of NaOH. This can be obtained as follow:

Volume = 500 mL = 500 / 1000 = 0.5 L
Molarity = 0.25 M
Mole of NaOH =?

Mole = Molarity x Volume

Mole of NaOH = 0.25 × 0.5

Mole of NaOH = 0.125 mole

<h3>How to determine the mass of sodium hydroxide, NaOH</h3>

The mass of NaOH needed can be obtained as follow:

Molar mass of NaOH = 40 g/mol
Mole of NaOH = 0.125 mole
Mass of NaOH =?

Mass = mole × molar mass

Mass of NaOH = 0.125 × 40

Mass of NaOH = 5 g

Thus, to prepare the solution, measure 5 g of NaOH and place it in a 500 mL volumetric flask and make it up to the mark with water.

Learn more about molarity:

brainly.com/question/15370276

#SPJ1

You might be interested in

Calculate the mole fraction of the total ions in an aqueous solution prepared by dissolving 0.400 moles of CaI2 in 850.0 g of wa

Evgesh-ka [11]

Answer:

0.00840

Explanation:

The computation of the mole fraction is as follow:

As we know that

Molar mass = Number of grams ÷ number of moles

number of moles = Number of grams ÷ molar mass

Given that

Number of moles of CaI2 = 0.400

And, Molar mass of water = 18.0 g/mol

Now Number of moles of water is

= 850.0 g ÷ 18.0 g/mol

= 47.22 mol

And, Total number of moles is

= 0.400 + 47.22

= 47.62

So, Molar fraction of CaI2 is

= 0.400 ÷ 47.62

= 0.00840

4 0

3 years ago

How many mols are present in 5.24 x 1024 atoms of Carbon tetra fluoride?

Free_Kalibri [48]

Answer: 5.44×10226.022140857(74)×1023⋅mol−1.

Explanation: So the answer is approx. 0.10⋅mol

3 0

2 years ago

Using principles of atomic structure, explain why the atomic radius of Te is less than the ionic radius of Te2− . Photoelectron

ValentinkaMS [17]

Answer:

See explanation

Explanation:

Let us recall that a negative ion is formed by addition of electrons to an atom. When electrons are added to the atom, greater interelectronic repulsion increases the size of the Te^2− hence it is greater in size than Te atom. Therefore, the ionic radius of Te^2− is greater than the atomic radius of Te.

In the second question, oxygen is positioned so far to the right because it has a far smaller nuclear charge compared to Te. Hence in the PES spectrum, the 1s sublevel of oxygen lies far to the right of that of Te.

3 0

2 years ago

29.47 mL of a solution of the acid HBr is titrated, and 72.90 mL of 0.2500-M NaOH is required to reach the equivalence point. Ca

Klio2033 [76]

The original concentration of the acid solution is 6.175 $\times$ 10^-4 mol / L.

<u>Explanation:</u>

Concentration is the ratio of solute in a solution to either solvent or total solution. It is expressed in terms of mass per unit volume

HBr + NaOH -----> NaBr + H2O

There is a 1:1 equivalence with acid and base.

Moles of NaOH = 72.90 $\times$ 10^-3 $\times$ 0.25

= 0.0182 mol.

[ HBr ] = moles of base / volume of a solution

= 0.0182 / 29.47

= 6.175 $\times$ 10^-4 mol / L.

4 0

2 years ago

Unit 1- Unit Assessment (Matter & Density)

konstantin123 [22]

Answer:

<h3>The answer is 11 g/mL</h3>

Explanation:

The density of a substance can be found by using the formula

$density = \frac{mass}{volume} \\$

From the question

mass = 3025 g

volume = 275 mL

We have

$density = \frac{3025}{275} \\$

We have the final answer as

Hope this helps you

7 0

2 years ago