0 84g of metal carbonate reacts completely with 40ml of H2SO4 .What is equivalent weight of the metal?

To find the equivalent weight of the metal in the carbonate that reacts with sulfuric acid (H2SO4), we need to follow a few logical steps. First, we should understand the reaction taking place and how to calculate the equivalent weight based on the information provided.

Understanding the Reaction

When a metal carbonate reacts with sulfuric acid, it typically produces a salt, water, and carbon dioxide. The general reaction can be represented as:

Metal Carbonate + H2SO4 → Salt + H2O + CO2

In this case, we have 0.84 grams of the metal carbonate reacting with 40 mL of sulfuric acid. To find the equivalent weight of the metal, we need to determine how many moles of H2SO4 are reacting and how many equivalents of the metal are involved in the reaction.

Calculating Moles of H2SO4

The first step is to calculate the number of moles of sulfuric acid used in the reaction. The molarity of sulfuric acid is not provided, but we can assume it is a standard concentration for calculations. For instance, if we assume it is 1 M (1 mole per liter), we can calculate the moles as follows:

• Volume of H2SO4 = 40 mL = 0.040 L
• Moles of H2SO4 = Molarity × Volume = 1 mol/L × 0.040 L = 0.040 moles

Determining the Reaction Stoichiometry

In the reaction between metal carbonate and sulfuric acid, typically, one mole of metal carbonate reacts with one mole of sulfuric acid to produce one mole of salt, one mole of water, and one mole of carbon dioxide. Therefore, the moles of metal carbonate will also be 0.040 moles.

Finding the Equivalent Weight

The equivalent weight of a substance is defined as the mass of the substance that will combine with or displace one mole of hydrogen ions (H+). For metal carbonates, the equivalent weight can be calculated using the formula:

Equivalent Weight = (Molar Mass of Metal Carbonate) / n

Here, 'n' is the number of moles of H+ ions that one mole of the metal carbonate can provide. In the case of a typical metal carbonate reacting with sulfuric acid, it usually provides two H+ ions (since it reacts with H2SO4). Therefore, n = 2.

Calculating Molar Mass of the Metal Carbonate

To find the molar mass of the metal carbonate, we can use the mass of the carbonate and the number of moles:

• Mass of metal carbonate = 0.84 g
• Moles of metal carbonate = 0.040 moles
• Molar Mass = Mass / Moles = 0.84 g / 0.040 moles = 21 g/mol

Final Calculation of Equivalent Weight

Now, we can calculate the equivalent weight:

Equivalent Weight = Molar Mass / n = 21 g/mol / 2 = 10.5 g/equiv

Thus, the equivalent weight of the metal in the carbonate is 10.5 grams per equivalent. This means that for every 10.5 grams of the metal carbonate, it can react with one mole of H+ ions from sulfuric acid.