1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
torisob [31]
3 years ago
8

How many grams of sodium hydroxide are needed to make 250. Ml of a 7.80 m solution?

Chemistry
2 answers:
sashaice [31]3 years ago
7 0
<h3><u>Answer;</u></h3>

= 78 g of NaOH

<h3><u>Explanation;</u></h3>

Concentration = Moles of solute/Volume of solution

Thus;

Moles of the solute = Volume × Concentration

                                = 7.80 Moles/L × 0.250 L

                                 = 1.95 moles

But; 1 mole of NaOH = 40.0 g

Thus;

Mass of NaOH = moles × molar mass

                         = 1.95 moles × 40 g/mole

                        <u> = 78 g of NaOH</u>

Mkey [24]3 years ago
3 0

78 g of NaOH

<h3>Further explanation</h3>

Given:

  • The concentration of the NaOH solution that we want to make is 7.8 M.
  • The volume of NaOH solution that we want to make is 250 ml.

Question:

How many grams of sodium hydroxide are needed to make 250 ml of a 7.80 M solution?

The Process:

Step-1

Let us prepare the relative molecular mass (Mr) of NaOH.

  • Relative atomic mass: Na = 23, O = 16, and H = 1
  • Relative molecular mass (Mr) of NaOH = 23 + 16 + 1 = 40.

Step-2

The concentration of the solution is a mole of solute divided by 1 liter of solution.

\boxed{ \ M = \frac{n}{V} \ }  (Remember V in liters here)

We know that mole is mass divided by molecular mass.

\boxed{ \ n = \frac{mass}{Mr} \ }

The relationship between concentration (M), mass, relative molecular mass (Mr), and volume of solution in ml (V) is as follows:

\boxed{ \ M = \frac{mass}{Mr} \times \frac{1,000}{V} \ } (Remember V in ml here)

Substitute all known data into the equation.

\boxed{ \ 7.80 = \frac{mass}{40} \times \frac{1,000}{250} \ }

\boxed{ \ 7.80 = \frac{mass}{40} \times 4 \ }

\boxed{ \ 7.80 = \frac{mass}{10} \ }

Mass = 7.80 x 10

Mass = 78

Thus, the number of grams of sodium hydroxide are needed to make 250 ml of a 7.80 M solution is 78 grams.

_ _ _ _ _ _ _ _ _ _

Notes:

The concentration of the solution, especially in this case molarity, represents one significant data. Among them play a role in

  • determining the pH value (acid, base, or salt),
  • determining the value of the equilibrium constant, and
  • calculating osmotic pressure.
<h3>Learn more</h3>
  1. What is the concentration of a solution formed by diluting 25.0 ml of a 3.2 M NaCl solution to 135.0 ml?  brainly.com/question/12452615
  2. An example of the dilution of a solution brainly.com/question/4516437  
  3. How many moles of hno3 are present in the dilute solution? brainly.com/question/13501499

You might be interested in
Fernanda looked at a sample of paint under a microscope. At right is the sketch she made of what she saw. Label A points to the
Degger [83]

Answer:dispersed state

dispersed medium

colloid

7 0
3 years ago
Read 2 more answers
A 11.97g sample of NaBr contains 22.34 % Na by mass. Considering the law of constant composition (definite proportions), how man
kap26 [50]
<h3>Answer:</h3>

2.125 g

<h3>Explanation:</h3>

We have;

  • Mass of NaBr sample is 11.97 g
  • % composition by mass of Na in the sample is 22.34%

We are required to determine the mass of 9.51 g of a NaBr sample.

  • Based on the law of of constant composition, a given sample of a compound will always contain the sample percentage composition of a given element.

In this case,

  • A sample of 11.97 g of NaBr contains 22.34% of Na by mass
  • Therefore;

A sample of 9.51 g of NaBr will also contain 22.345 of Na by mass

  • But;

% composition of an element by mass = (Mass of element ÷ mass of the compound) × 100

  • Therefore;

Mass of the element = (% composition of an element × mass of the compound) ÷ 100

Therefore;

Mass of sodium = (22.34% × 9.51 g) ÷ 100

                         = 2.125 g

Thus, the mass of sodium in 9.51 g of NaBr is 2.125 g

3 0
3 years ago
2Fe + 3C02<br> 3CO + Fe2O3<br> AH = -24.7 kJ<br> Is the reaction exothermic or endothermic?
Softa [21]

Answer:

the answer should be B xD<<<<<<<<<<<:::::::::::>>>>>>>>::::::::::::<<<<<<:::::>>>>>::::: makes this brainlist for good luck for the rest of ur life dont risk it

Explanation:

7 0
3 years ago
An experiment produced 0.10 g CO2, with a volume of 0.056 L at STP. If the accepted density of CO2 at STP is 1.96 g/L, what is t
Pachacha [2.7K]
The density of CO2 getting from experiment is 0.1/0.056 = 1.79 g/L. The percent error of this is (1.96 -1.79)/1.96*100%=8.67%. So the approximate percent error is 8.67%.
3 0
3 years ago
Draw the structure of 4-methyl-5-oxohexanal.
aniked [119]

Answer:

Explanation:

The structural formula provides more information which is often used to represent a particular organic substance. A structural formula indicates how the atoms are arranged within the molecule of a substance. From the information, the structure of  4-methyl-5-oxohexanal is represented by using a stick formula where the methyl group falls into position 4 and oxygen group falls into position 5 on the hexanal compound.

The structure is provided in the image attached below for better understanding.

4 0
3 years ago
Other questions:
  • How long it takes a 100 watt light bulb to use 10,000 J of electrical energy?​
    11·1 answer
  • What is the most effective way to differentiate between potassium feldspar and plagioclase feldspar?
    13·1 answer
  • How much energy is released when 50.00 mol of glycerin melts? (Heat of fusion glycerin-91.7 KJ/mol)
    14·1 answer
  • Zinc reacts with hydrochloric acid according to the reaction equation Zn ( s ) + 2 HCl ( aq ) ⟶ ZnCl 2 ( aq ) + H 2 ( g ) How ma
    10·1 answer
  • How do decantation and filtration differ which should be faster
    14·1 answer
  • What is the molecular geometry if you have 3 single bonds and 1 lone pair around the central atom?
    9·1 answer
  • describe the general trend in electronegativity as metals in group 2 on the periodic table are concidered in order of increasing
    13·1 answer
  • Andrew gathered several different species of seed plants. Which three characteristics do all the plants most likely
    8·2 answers
  • crash course video about periodic table - The Periodic Table: Crash Course Chemistry #4 - write a reflection about this video
    11·1 answer
  • Plan an investigation using solid and liquid water to show that thermal energy is not the same as temperature.
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!