Unbalanced it should be 2Zn+2Hcl=2ZnCl2+H2
Answer:
repetition
Explanation:
Taking an average of 16 height measurements is an example of repetition. Repetition involves making and taking repeated measurements in an experiment.
The goal is to achieve a highly accurate and precise data from the experiment.
- Replication involves duplicating another experiment and testing to see how valid they are.
- Since Veronica's experiment is a brand new one, it's hypothesis has not been tested or replicated in any way.
- Therefore, it is not a replication.
- But she is repeating the experiment to obtain different values.
<span>12.4 g
First, calculate the molar masses by looking up the atomic weights of all involved elements.
Atomic weight manganese = 54.938044
Atomic weight oxygen = 15.999
Atomic weight aluminium = 26.981539
Molar mass MnO2 = 54.938044 + 2 * 15.999 = 86.936044 g/mol
Now determine the number of moles of MnO2 we have
30.0 g / 86.936044 g/mol = 0.345081265 mol
Looking at the balanced equation
3MnO2+4Al→3Mn+2Al2O3
it's obvious that for every 3 moles of MnO2, it takes 4 moles of Al. So
0.345081265 mol / 3 * 4 = 0.460108353 mol
So we need 0.460108353 moles of Al to perform the reaction. Now multiply by the atomic weight of aluminum.
0.460108353 mol * 26.981539 g/mol = 12.41443146 g
Finally, round to 3 significant figures, giving 12.4 g</span>
There will be needed 982.35 mL of solution to obtain 16.1 grams of the salt.There will be needed mL of
Why?
In order to calculate how many milliliters are needed to obtain 16.1 grams of the salt given its concentration, we first need to find its chemical formula which is the following:

Now that we know the chemical formula of the substance, we need to find its molecular mass. We can do it by the following way:

We have that the molecular mass of the substance will be:

Therefore, knowing the molecular mass of the substance, we need to calculate how many mols represents 16.1 grams of the same substance, we can do it by the following way:


Finally, if we need to calculate how many milliliters are needed, we need to use the following formula:


Now, substituting and calculating, we have:

Henc, there will be needed 982.35 mL of solution to obtain 16.1 grams of the salt.
Have a nice day!