Answer:
You can increase the validity of an experiment by controlling more variables, improving measurement technique, increasing randomization to reduce sample bias, blinding the experiment, and adding control or placebo groups.
Answer:
Mass = 10.1 g
Explanation:
Given data:
Mass of Fe₂O₃ produced = ?
Mass of iron rust = 12.0 g
Solution:
Chemical equation:
4Fe + 3O₂ → 2Fe₂O₃
Number of moles of iron:
Number of moles = mass/ molar mass
Number of moles = 12.0 g/ 55.85 g/mol
Number of moles = 0.215 mol
Now we will compare the moles of iron and Fe₂O₃ .
Fe : Fe₂O₃
4 : 2
0.215 : 2/4×0.125 = 0.063 mol
Mass of Fe₂O₃ :
Mass = number of moles × molar mass
Mass = 0.063 mol × 159.7 g/mol
Mass = 10.1 g
P2 = 54.6 kPa
Explanation:
Given:
V1 = 10.0 L. V2 = 50.0 L
P1 = 273 kPa. P2 = ?
We can use Boyle's law to solve this problem.
P1V1 = P2V2
Solving for P2,
P2 = (V1/V2)P1
= (10.0 L/50.0 L)(273 kPa)
= 54.6 kPa
Answer:
3 fluorine atoms will be present