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Sodium metal reacts with sulfuric acid. The balanced equation is: 2Na + H2SO4 --> Na2SO4 + H2

Calculate the mass of sodium needed to produce 100g of hydrogen gas.

[Relative atomic masses:
H =1; Na =23]

User Gaurang
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2 Answers

4 votes

Answer:A balanced chemical equation provides a great deal of information in a very succinct format. Chemical formulas

provide the identities of the reactants and products involved in the chemical change, allowing classification of the

reaction. Coefficients provide the relative numbers of these chemical species, allowing a quantitative assessment

of the relationships between the amounts of substances consumed and produced by the reaction. These quantitative

relationships are known as the reaction’s stoichiometry, a term derived from the Greek words stoicheion (meaning

“element”) and metron (meaning “measure”). In this module, the use of balanced chemical equations for various

stoichiometric applications is explored.

The general approach to using stoichiometric relationships is similar in concept to the way people go about many

common activities. Food preparation, for example, offers an appropriate comparison. A recipe for making eight

pancakes calls for 1 cup pancake mix, 3

4

cup milk, and one egg. The “equation” representing the preparation of

pancakes per this recipe is

1 cup mix + 3

4

cup milk + 1 egg ⟶ 8 pancakes

If two dozen pancakes are needed for a big family breakfast, the ingredient amounts must be increased proportionally

according to the amounts given in the recipe. For example, the number of eggs required to make 24 pancakes is

24 pancakes ×

1 egg

8 pancakes = 3 eggs

Balanced chemical equations are used in much the same fashion to determine the amount of one reactant required to

react with a given amount of another reactant, or to yield a given amount of product, and so forth. The coefficients in

the balanced equation are used to derive stoichiometric factors that permit computation of the desired quantity. To

illustrate this idea, consider the production of ammonia by reaction of hydrogen and nitrogen:

N2

(g) + 3H2

(g) ⟶ 2NH3

(g)

This equation shows ammonia molecules are produced from hydrogen molecules in a 2:3 ratio, and stoichiometric

factors may be derived using any amount (number) unit:

2 NH3 molecules

3 H2 molecules or

2 doz NH3 molecules

3 doz H2 molecules or

2 mol NH3 molecules

3 mol H2 molecules

These stoichiometric factors can be used to compute the number of ammonia molecules produced from a given

number of hydrogen molecules, or the number of hydrogen molecules required to produce a given number of

ammonia molecules. Similar factors may be derived for any pair of substances in any chemical equation.

Step-by-step explanation:

User DaveRGP
by
7.4k points
2 votes

Answer:

2.3 kg.

Step-by-step explanation:

The balanced equation tells us that 2 moles of sodium (Na) reacts with 1 mole of sulfuric acid (H2SO4) to produce 1 mole of hydrogen gas (H2).

To calculate the mass of sodium needed to produce 100g of hydrogen gas, we need to use the following steps:

Calculate the number of moles of hydrogen gas produced from 100g of hydrogen gas.

Use the mole ratio from the balanced equation to determine the number of moles of sodium required to produce that amount of hydrogen gas.

Convert the moles of sodium to grams using the molar mass of sodium.

Step 1:

The molar mass of hydrogen gas (H2) is 2 g/mol. Therefore, 100g of hydrogen gas is equal to 100/2 = 50 moles of H2.

Step 2:

From the balanced equation, 2 moles of Na reacts with 1 mole of H2. So, the number of moles of Na required to produce 50 moles of H2 is:

2 moles Na / 1 mole H2 = 2 * 50 = 100 moles Na

Step 3:

The molar mass of sodium (Na) is 23 g/mol. Therefore, the mass of sodium required to produce 100g of hydrogen gas is:

100 moles Na * 23 g/mol = 2300g or 2.3 kg of Na

Therefore, the mass of sodium needed to produce 100g of hydrogen gas is 2.3 kg.

User Bimasakti
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7.8k points