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5.4g of aluminum reacts with sulfuric acid (H₂SO4) to form aluminum sulfate and hydrogen.

a. Write the chemical equation.
b. Find mass of required sulfuric acid.
C. Find volume of the obtained gas.
(AI=23, S = 32, O=16, H =1, 2g of H2 has 22.4L).​

User Tjm
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1 Answer

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Answer:

a. The chemical equation for the reaction is:

2Al + 3H₂SO₄ → Al₂(SO₄)₃ + 3H₂

b. To find the mass of required sulfuric acid, we need to use stoichiometry. We can start by finding the number of moles of aluminum used in the reaction:

Molar mass of Al = 27 g/mol

Number of moles of Al = 5.4 g / 27 g/mol = 0.2 mol

According to the balanced equation, 3 moles of H₂SO₄ are required to react with 2 moles of Al. Therefore, the number of moles of H₂SO₄ required is:

Number of moles of H₂SO₄ = 3/2 x 0.2 mol = 0.3 mol

Molar mass of H₂SO₄ = 2 x 1 g/mol + 32 g/mol + 4 x 16 g/mol = 98 g/mol

Mass of H₂SO₄ required = 0.3 mol x 98 g/mol = 29.4 g

Therefore, 29.4 g of sulfuric acid is required to react with 5.4 g of aluminum.

c. To find the volume of hydrogen gas obtained, we need to use the ideal gas law:

PV = nRT

where P is the pressure of the gas, V is its volume, n is the number of moles of the gas, R is the universal gas constant (0.0821 L atm/mol K), and T is the temperature in Kelvin.

We can start by finding the number of moles of hydrogen gas produced in the reaction. According to the balanced equation, 3 moles of H₂ are produced for every 2 moles of Al. Therefore, the number of moles of H₂ produced is:

Number of moles of H₂ = 3/2 x 0.2 mol = 0.3 mol

Assuming the reaction occurs at standard temperature and pressure (STP), which is 0°C (273 K) and 1 atm, we can use the molar volume of a gas at STP, which is 22.4 L/mol. Therefore:

V = nRT/P = 0.3 mol x 0.0821 L atm/mol K x 273 K / 1 atm = 6.58 L

Therefore, the volume of hydrogen gas produced at STP is 6.58 L.

Step-by-step explanation:

User Ben Lin
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