Hydrochloric acid reacts with Magnesium to form Magnesium Chloride and Hydrogen gas. deltaH= -442kJ

If 15mL of 1.0M HCl reacts with .3g of Mg, how many L of H2 are produced? How much heat is produced?

balance the equation

Mg+ 2HCl>> MgCl2 +H2 deltaH= -442kJ/mole

so the question is, what is number of moles of Mg reacting?

Determine the moles of each reactant
mg=.3/atomimassMg
HCL=1M*.015 moles

Do you have 2 times the moles of HCl as Mg? If so, Mg is the limiting reactant, if not, HCl is the limiting reactant.

In either case, you must determine how many moles of Mg reacts.

Heat= Hr*molesMg

To determine how many liters of H2 gas are produced and how much heat is produced in this reaction, we can use stoichiometry and the given information.

First, let's write the balanced chemical equation for the reaction between hydrochloric acid (HCl) and magnesium (Mg):

2 HCl + Mg -> MgCl2 + H2

According to the balanced equation, 2 moles of HCl react with 1 mole of Mg and produce 1 mole of H2.

Now, let's calculate the moles of HCl using its volume and concentration:

Given:
Volume of HCl solution = 15 mL
Concentration of HCl solution = 1.0 M

To convert the volume into liters, we divide it by 1000:
15 mL / 1000 = 0.015 L

Using the formula for moles (moles = volume x concentration), we can calculate the moles of HCl:
moles of HCl = 0.015 L x 1.0 M = 0.015 moles

Next, we need to determine the moles of Mg given its mass:

Given:
Mass of Mg = 0.3 g

To determine the moles of Mg, we need its molar mass. The molar mass of Mg is 24.31 g/mol.

moles of Mg = 0.3 g / 24.31 g/mol = 0.012 moles

Since the reaction is in a 1:1 ratio between moles of HCl and moles of H2, we can conclude that 0.015 moles of HCl would produce 0.015 moles of H2.

To convert moles of H2 to liters, we use the ideal gas law:

PV = nRT

Since the volume (V) of H2 is unknown, we can calculate it by rearranging the equation:

V = (nRT) / P

Assuming the reaction is taking place at standard temperature and pressure (STP):
Temperature (T) = 273 K
Pressure (P) = 1 atm

Substituting the values into the equation, we have:
V = (0.015 moles x 0.0821 L·atm/mol·K x 273 K) / 1 atm
V = 0.328 L

Therefore, approximately 0.328 liters of H2 gas are produced in the reaction.

To calculate the heat produced (deltaH), we can use the given value of -442 kJ.

The reaction produces 0.015 moles of H2 gas. Therefore, to calculate the heat produced per mole of H2 gas, we divide -442 kJ by 0.015 moles:

Heat produced per mole of H2 = -442 kJ / 0.015 moles = -29467 kJ/mol

Hence, the heat produced in the reaction is approximately -29467 kJ/mol.

It's important to note that the negative sign indicates that the reaction is exothermic, meaning it releases heat.