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2 years ago

Sodium metal and water react to form sodium hydroxide and hydrogen gas:

Chemistry

1 answer:

asambeis [7]2 years ago

8 0

Answer:

Mass of sodium react = 8.63 g

Explanation:

Given data:

Mass of sodium hydroxide produced = 15 g

Mass of sodium react = ?

Solution:

Chemical equation:

2Na + 2H₂O → H₂ + 2NaOH

Number of moles of sodium hydroxide:

Number of moles = mass/ molar mass

Number of moles = 15 g/ 40 g/mol

Number of moles = 0.375 mol

Now we will compare the moles of Sodium and sodium hydroxide.

NaOH : Na

2 : 2

0.375 : 0.375

Mass of Sodium:

Mass = number of moles × molar mass

Mass = 0.375 mol× 23 g/mol

Mass = 8.63 g

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Complete Question

The complete question is shown on the first uploaded image

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