A chemist wishes to determine the rate of reaction of zinc with hydrochloric acid. The equation for the reaction is:
Zn(s) + 2HCl(aq) ---> H2(g) + ZnCl2(aq)
A piece of zinc is dropped into 1.00 L of 0.100 M HCl and the following data were obtained:
Time/Mass of Zinc
0 s/0.016 g
4 s/0.014 g
8 s/0.012 g
12 s/0.010 g
16 s/0.008 g
20 s/0.006 g
If the rate of consumption of magnesium is 5.0 x 10-9 mol/s, find the rate of
consumption of HCl in moles/s.
oops sorry i meant if the rate of comsumption of ZINC is 5.0 x 10^-9 mol/s...
To determine the rate of consumption of HCl in moles/s, we need to calculate the change in the number of moles of HCl consumed over a certain time interval.
First, we need to convert the given mass of zinc consumed to moles. The molar mass of zinc (Zn) is 65.38 g/mol.
The change in moles of zinc can be calculated using the following formula:
Change in moles of zinc (Δn) = (Final mass of zinc - Initial mass of zinc) / Molar mass of zinc
For the given data:
Δn = (0.006 g - 0.016 g) / 65.38 g/mol
Δn = -0.01 g / 65.38 g/mol
Δn = -1.53 x 10^-4 mol
Since 1 mole of zinc reacts with 2 moles of HCl, the change in moles of HCl consumed will be twice the change in moles of zinc consumed:
Change in moles of HCl = 2 * Δn
Change in moles of HCl = 2 * (-1.53 x 10^-4 mol)
Change in moles of HCl = -3.06 x 10^-4 mol
Since the rate of consumption of zinc is given as 5.0 x 10^-9 mol/s, we can use the stoichiometry of the reaction to calculate the rate of consumption of HCl.
Rate of consumption of HCl = (Rate of consumption of zinc / 2) * 2
Rate of consumption of HCl = (5.0 x 10^-9 mol/s / 2) * 2
Rate of consumption of HCl = 5.0 x 10^-9 mol/s
Therefore, the rate of consumption of HCl is 5.0 x 10^-9 mol/s.
To find the rate of consumption of HCl in moles/s, we need to determine the change in the number of moles of HCl consumed per second.
First, we need to determine the change in the mass of zinc per second using the given data. We can use the equation:
Rate of consumption of zinc per second (in grams) = (mass of zinc at time t2 - mass of zinc at time t1) / (time t2 - time t1)
Using the given data:
From 0 s to 4 s:
Rate of consumption of zinc per second = (0.014 g - 0.016 g) / (4 s - 0 s)
From 4 s to 8 s:
Rate of consumption of zinc per second = (0.012 g - 0.014 g) / (8 s - 4 s)
From 8 s to 12 s:
Rate of consumption of zinc per second = (0.010 g - 0.012 g) / (12 s - 8 s)
From 12 s to 16 s:
Rate of consumption of zinc per second = (0.008 g - 0.010 g) / (16 s - 12 s)
From 16 s to 20 s:
Rate of consumption of zinc per second = (0.006 g - 0.008 g) / (20 s - 16 s)
Next, we need to convert the mass of zinc consumed per second to the number of moles of zinc consumed per second using the molar mass of zinc. The molar mass of zinc is 65.38 g/mol.
Rate of consumption of zinc per second (in moles) = (Rate of consumption of zinc per second (in grams)) / (molar mass of zinc)
Now, we can use the stoichiometry of the balanced chemical equation to determine the rate of consumption of HCl per second. From the balanced equation, we know that 1 mole of zinc reacts with 2 moles of HCl.
Rate of consumption of HCl per second (in moles) = 2 * Rate of consumption of zinc per second (in moles)
Finally, we can use the rate of consumption of magnesium given in the question to find the rate of consumption of HCl. The rate of consumption of magnesium is given as 5.0 x 10^-9 mol/s.
Rate of consumption of HCl per second (in moles) = (Rate of consumption of HCl per second (in moles)) / (Rate of consumption of magnesium per second (in moles))
Substituting the values calculated earlier:
Rate of consumption of HCl per second (in moles) = 2 * (Rate of consumption of zinc per second (in moles)) / (Rate of consumption of magnesium per second (in moles))
Please note that the calculations can be performed once the values for the rates of consumption of zinc per second (in grams) have been determined.