16.7 grams of chlorine gas are allowed to react with with 3.31 grams of water

What is the maximum amount of hydrochloric acid that can be formed in grams

For the following reaction, 20.8 grams of iron are allowed to react with with 4.82 grams of oxygen gas.

iron (s) + oxygen (g) iron(II) oxide (s)

What is the maximum amount of iron(II) oxide that can be formed? grams

What is the FORMULA for the limiting reagent?

What amount of the excess reagent remains after the reaction is complete? grams

For the first one, you have a stoichiometry problem. Here is a solve example. Just follow the steps.

http://www.jiskha.com/science/chemistry/stoichiometry.html

For the second one, this is a limiting reagent problem. You know that because BOTH (and not just one) of the reactants are given. What you do is to solve two stoichiometry problems, just as in your first one, then use the one producing the smaller value. The reagent producing the smaller value will be the limiting reagent; take that one, convert to moles of the non-limiting reagent, and subtract from the initial amount.

To determine the maximum amount of hydrochloric acid that can be formed, we need to determine which reactant is limiting and which is in excess.

First, let's calculate the number of moles for each reactant using their respective molar masses:

Molar mass of chlorine (Cl2) = 35.5 g/mol
Number of moles of chlorine = mass / molar mass = 16.7 g / 35.5 g/mol ≈ 0.470 moles

Molar mass of water (H2O) = 18.0 g/mol
Number of moles of water = mass / molar mass = 3.31 g / 18.0 g/mol ≈ 0.184 moles

Next, let's write a balanced equation for the reaction:

Cl2 + H2O -> HCl + HClO

From the balanced equation, we can see that 1 mole of chlorine (Cl2) reacts with 1 mole of water (H2O) to produce 2 moles of hydrochloric acid (HCl).
Therefore, the stoichiometric ratio is 1:1:2 for Cl2 : H2O : HCl.

Now, let's compare the number of moles of chlorine with the number of moles of water:

Number of moles of chlorine: 0.470 moles
Number of moles of water: 0.184 moles

Since the ratio of chlorine to water is 1:1, we can see that chlorine is the limiting reactant because it has fewer moles.

To calculate the maximum amount of hydrochloric acid that can be formed, we will use the number of moles and the molar mass of HCl:

Molar mass of HCl = 36.5 g/mol (H: 1.0 g/mol + Cl: 35.5 g/mol)

Number of moles of hydrochloric acid = 2 x number of moles of chlorine (based on the balanced equation) = 2 x 0.470 moles = 0.940 moles

Finally, we can calculate the maximum mass of hydrochloric acid:

Mass of hydrochloric acid = number of moles x molar mass = 0.940 moles x 36.5 g/mol ≈ 34.3 grams

Therefore, the maximum amount of hydrochloric acid that can be formed is approximately 34.3 grams.