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How many atoms in 40.0 grams of sodium hydroxide

1 Answer

5 votes

Answer:There are

6.022×10(to the power of 23)

atoms in 40.0 grams of sodium hydroxide.

Step-by-step explanation:

To find the number of atoms in a given amount of substance, you can use the concept of moles and Avogadro's number. Avogadro's number is approximately

6.022

×

1

0

23

6.022×10

23

atoms/mol.

Find the molar mass of sodium hydroxide (NaOH).

Sodium (Na) has a molar mass of approximately 22.99 g/mol.

Oxygen (O) has a molar mass of approximately 16.00 g/mol.

Hydrogen (H) has a molar mass of approximately 1.01 g/mol.

22.99

g/mol

+

16.00

g/mol

+

1.01

g/mol

=

40.00

g/mol

22.99g/mol+16.00g/mol+1.01g/mol=40.00g/mol.

Calculate the number of moles using the formula:

moles

=

mass

molar mass

=

40.0

g

40.00

g/mol

=

1.00

mol

moles=

molar mass

mass

=

40.00g/mol

40.0g

=1.00mol

Use Avogadro's number to find the number of atoms:

number of atoms

=

moles

×

(

6.022

×

1

0

23

atoms/mol

)

number of atoms=moles×(6.022×10

23

atoms/mol)

number of atoms

=

1.00

mol

×

(

6.022

×

1

0

23

atoms/mol

)

=

6.022

×

1

0

23

number of atoms=1.00mol×(6.022×10

23

atoms/mol)=6.022×10

23

User Aldjinn
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