Zinc combines with hydrochloric acid to form aqueous zinc chloride and hydrogen gas. If 300.0 mL of a 0.150 M solution of HCl is allowed to react with excess zinc, how many moles of hydrogen gas would be produced? Part two: if this reaction happens at STP what volume of hydrogen gas is produced? (write a balanced equation first)
Sure, here's the balanced equation for the reaction:
Zn + 2HCl → ZnCl₂ + H₂
Now, let's solve part one:
Given:
Volume of HCl solution = 300.0 mL = 0.3000 L
Molarity of HCl solution = 0.150 M
From the balanced equation, we can see that 1 mole of Zn reacts with 2 moles of HCl to produce 1 mole of H₂.
Using the formula: Molarity (M) = moles/volume (L)
moles of HCl = Molarity × volume
moles of HCl = 0.150 M × 0.3000 L = 0.045 moles
Since 1 mole of Zn reacts to produce 1 mole of H₂, we can conclude that 0.045 moles of HCl will produce 0.045 moles of H₂.
Now, let's move on to part two:
At STP (Standard Temperature and Pressure), 1 mole of any gas occupies 22.4 L.
So, 0.045 moles of H₂ would occupy:
0.045 moles × 22.4 L/mole = 1.008 L
Therefore, at STP, 1.008 liters of hydrogen gas would be produced.
Remember, it's always important to note the conditions (like STP) while solving stoichiometry problems. I hope this helps while keeping a smile on your face!
The balanced equation for the reaction between zinc and hydrochloric acid is:
Zn + 2HCl -> ZnCl2 + H2
To find the number of moles of hydrogen gas produced, we need to use the equation:
moles = concentration x volume
Part One: Finding moles of hydrogen gas produced
Given:
- Volume of HCl solution = 300.0 mL = 0.300 L
- Concentration of HCl solution = 0.150 M (moles per liter)
Using the equation: moles = concentration x volume
moles of HCl = 0.150 M x 0.300 L
moles of HCl = 0.045 moles
From the balanced equation, we know that 1 mole of HCl produces 1 mole of H2.
So, the number of moles of hydrogen gas produced is also 0.045 moles.
Part Two: Finding volume of hydrogen gas at STP
STP (Standard Temperature and Pressure) conditions are defined as a temperature of 0 degrees Celsius (273.15 K) and a pressure of 1 atmosphere.
1 mole of any ideal gas at STP occupies 22.4 L.
So, the volume of hydrogen gas produced at STP is:
volume = moles x 22.4 L/mol
volume = 0.045 moles x 22.4 L/mol
volume = 1.008 L
Therefore, if the reaction occurs at STP, 1.008 liters of hydrogen gas would be produced.
First, let's write the balanced equation for the reaction:
Zn + 2HCl -> ZnCl2 + H2
To find the number of moles of hydrogen gas produced, we need to use stoichiometry. The equation tells us that for every 1 mole of zinc, 1 mole of hydrogen gas is produced. This means that the number of moles of hydrogen gas produced will be equal to the number of moles of zinc consumed.
To find the number of moles of zinc consumed, we can use the given concentration and volume of hydrochloric acid:
0.150 M represents 0.150 mol/L. So, to find the number of moles of hydrochloric acid in the solution, we can multiply the concentration by the volume:
0.150 mol/L * 0.300 L = 0.045 moles of HCl
Since zinc is in excess, it will be completely consumed in the reaction. Therefore, the number of moles of hydrogen gas produced will also be 0.045 moles.
Now, let's move on to part two of the question, where we need to find the volume of hydrogen gas produced at STP (standard temperature and pressure). STP is defined as 273.15 K (0°C) and 1 atmosphere (atm) of pressure.
To calculate the volume of gas at STP, we can use the ideal gas law, which states:
PV = nRT
Where:
P = Pressure (in atm)
V = Volume (in liters)
n = Number of moles
R = Ideal gas constant (0.0821 L·atm/K·mol)
T = Temperature (in Kelvin)
In this case, we have the number of moles (0.045) and the temperature (273.15 K). We also know that at STP the pressure is 1 atm.
Plugging these values into the equation, we can solve for V:
V = (nRT) / P
= (0.045 mol * 0.0821 L·atm/K·mol * 273.15 K) / 1 atm
= 1.148 L
Therefore, at STP, the volume of hydrogen gas produced will be approximately 1.148 Liters.
Write and balanced the equation.
Zn + 2HCl ==> ZnCl2 + H2
How many moles HCl do you have? That's M x L = 0.150 x 0.300 = ??
Use the equation to convert mols HCl to moles H2.
mols H2 = moles HCl x (1 mol H2/2 mols HCl) = moles HCl x (1/2) = ? = moles H2.
If at STP, the volume will be
?mols H2 x 22.4 L/mol = ? L H2 @ STP.