Sodium hydroxide, naoh, is a strong base that is used in industrial synthesis and processes such as making paper. what is the mass

Sodium hydroxide, naoh, is a strong base that is used in industrial synthesis and processes such as making paper. what is the mass of 2.80 ×1022 molecules of naoh (molar mass = 40.0 g/mol)?

Answers

1.86 g

Explanation:

We must convert formula units of NaOH to moles and then to mass of NaOH.

Step 1. Convert molecules to moles

text{Moles of NaOH} = 2.80 times 10^{22}text{ units NaOH} times frac{ text{1 mol NaOH}}{ 6.022 times 10^{23} text{ units NaOH}} = text{0.046 50 mol NaOH}

Step 2. Convert moles to grams

text{Mass of NaOH} = text{0.046 50 mol NaOH} times frac{text{40.0 g NaOH} }{ text{1 mol NaOH}} = text{1.86 g NaOH}

Mass of 2.80times 10^{22}  molecules of NaOH = 1.86 g

Explanation:

Avogadro’s number represent the number of the constituent particles which are present in one mole of the substance. It is named after scientist Amedeo Avogadro and is denoted by N_0.

Avogadro constant:-

N_a=6.023times 10^{23}

So,

6.023times 10^{23}  molecules of NaOH are present in 1 mole of NaOH

Given, Molar mass of NaOH = 40.0 g/mol

This means, mass of 1 mole of NaOH = 40 g

So,

6.023times 10^{23}  molecules of NaOH weighs 40 g

1  molecule of NaOH weighs frac{40}{6.023times 10^{23}} g

2.80times 10^{22}  molecules of NaOH weighs frac{40}{6.023times 10^{23}}times 2.80times 10^{22} g

Mass of 2.80times 10^{22}  molecules of NaOH = 1.86 g

                  Mass of NaOH =  1.594 g

Solution:

Data Given:

                 Number of Molecules  =  2.40 × 10²²

                 M.Mass of NaOH  =  40.0 g.mol⁻¹

                 Mass of NaOH  =  ?

Step 1: Calculate Moles of NaOH;

  Moles  =  Number of Molecules ÷ 6.022 × 10²³ Molecules.mol⁻¹

Putting value,

  Moles  =   2.40 × 10²² Molecules ÷ 6.022 × 10²³ Molecules.mol⁻¹

                   Moles  =  0.04 mol

Step 2: Calculate Mass of NaOH;

                   Moles  =  Mass ÷ M.Mass

Solving for Mass,

                   Mass  =  Moles × M.Mass

Putting values,

                   Mass  =  0.04 mol × 40.0 g.mol⁻¹

                   Mass  =  1.594 g

1.46 g

Explanation:

For this exercise we need the Avogadro’s number that represents the number of molecules that has a mole of a substance and is value is 6.022x10^23. That is to say that 1 mole of NAOH has  6.022x10^23 molecules and by a rule of three we have:

1 mole NaOH ----------- 6.022x10^23 molecules

         X             ----------- 2.20x10^22 molecules

X=frac{(2.20x10^{22}molecules)(1moleNaOH)}{6.022x10^{23}molecules}

X = 0.0365 moles NaOH

Then, 2.20x10^22 molecules of NaOH represent 0.0365 moles of NaOH.

To find the mass we use another rule of three with the NaOH molar mass:

1 mole NaOH             ------ 40.0 g

0.0365 moles NaOH ------ X

X=frac{(0.0365 moles NaOH)(40.0 g)}{1 mole NaOH}

X= 1.46 g

So, 0.0365 moles of NaOH have a mass of 1.46 g or 2.20 ×10^22 molecules of NaOH have a mass of 1.46 g

1.792 g

Explanation:

We are given;

Formula units of NaOH as 2.70 ×10^22 Molar mass of NaOH as 40.0 g/mol

We are required to determine the mass of NaOH in the given formula units;

Step 1: Determine the number of moles of NaOHWe need to know that 1 mole of a compound contains formula units equivalent to the Avogadro's number, 6.022 × 10^23.Therefore;

1 mole of NaOH = 6.022 × 10^23 formula units

Thus;

Moles of NaOH = 2.70 ×10^22 ÷  6.022 × 10^23 formula units/mol

                          = 0.0448 moles      

Step 2: Determine the mass of NaOH

Moles = mass ÷ Molar mass

Therefore,

Mass = Moles × Molar mass

        = 0.0448 moles × 40.0 g/mol

        = 1.792 g

Thus, the mass of 2.70 × 10^22 formula units of NaOH is 1.792 g

1.926 g of NaOH

Explanation:

Concept tested: Mole and Avogadro's number

We need to know that , 1 mole of a compound contains number of molecules equivalent to the Avogadro's number.Th Avogadro's number is 6.022 × 10^23

Therefore;

1 mole of a compound = 6.022 × 10^23 molecules

In this case; Our compound is NaOH

Therefore;

1 mole of NaOH contains 6.022 × 10^23 molecules

But; Molar mass of NaOH is 40.0 g/mol

Therefore;

40.0 g of NaOH contains 6.022 × 10^23 molecules

With this we can calculate the mass of 2.90 × 10^22 molecules

Mass of a compound = (number of molecules ÷ Avogadro's constant) × molar mass

Therefore;

Mass of NaOH =(2.90 × 10^22 molecules ÷ 6.022 × 10^23 molecules)40g

                        = 1.9263 g

                        = 1.926 g NaOH

Thus, the mass of NaOH is 1.926 g

a. 3,6x10⁻⁴ moles

b. 1,096M

c. 1,53 g of NaOH

Explanation:

a. Theobromine has a molar mass of:

C: 12,01×7= 84,07 g/mol

H: 1,01×8= 8,08 g/mol

N: 14×4= 56,04 g/mol

O: 16×2= 32 g/mol

84,07 g/mol + 8,08 g/mol + 56 g/mol + 32 g/mol = 180,15g/mol. Thus, in 0,064g of theobromine are:

0,064g * frac{1mol}{180,15g} = 3,6x10⁻⁴ moles -two significant figures-

b. Molar mass of H₂SO₄ is 98,079 g/mol.

151,1g are:

151,1g * frac{1mol}{98,079g} = 1,54 moles of H₂SO₄

As molarity is moles of solute per liters of solution, molarity is:

1,54 moles of H₂SO₄ / 1,405L = 1,096 M

c. 2,30x10²² molecules of NaOH are:

2,30x10²²molecules × (1mol/6,022x10²³molecules) = 0,0382 moles of NaOH

As molar mass of NaOH is 40,04g/mol:

0,0382 moles* frac{40,04g}{1mol} = 1,53 g of NaOH

I hope it helps!

Answer : Mass would be = 1.859 g for NaOH

Explanation :  We have got 2.88 X  10^{22} molecules of NaOH,

so we get,

frac{2.88 X 10^{22} moles of NaOH }{6.022 X 10^{23}/mol } X 40.0 g of NaOH/mol

On solving we get, answer as 1.859 g

Hence the g of NaOH will be 1.86.

Avagadros number/ constant states that there are 6.022 x 10²³ units making up 1 mol of any substance. 
In NaOH - there are 6.022 x 10²³ NaOH molecules in 1 mol of NaOH
Mass of 1 mol of NaOH - 40 g
therefore 6.022 x 10²³ molecules weigh - 40 g
Then 2.60 x 10²² molecules - 40 x  2.60 x 10²² / (6.022 x 10²³ ) 
   mass is then - 1.73 g 
Molar mass NaOH = 40.0 g/mol

40.0 g 6.02x10²³ molecules
?? g 2.40x10²² molecules

2.40x10²² x ( 40.0 ) / 6.02x10²³ =

9.6x10²³ / 6.02x10²³ => 1.594 g

hope this helps!

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