A) because when gas is produced it changes chemical form whereas the chemical change is obvious.
C, erosion. Erosion is the natural process of breaking down natural products through wind, or similar natural resources.
Answer:
A) 3.6 cm
Explanation:
Accuracy comes down to how precisely you can read the length on a given scale. Here since the smallest increment is centimeter, we can go only one decimal beyond to estimate. This is because you can usually estimate to only one decimal place beyond the closest marks on any measuring.
So, the answer should be 3.6 cm.
Here's a document that explains it well: https://www.auburn.wednet.edu/cms/lib03/WA01001938/Centricity/Domain/1360/1_Uncertainty.pdf
Hope that's right!
The moles of oxygen gas (O2) that is needed is 4 moles
Explanation
2H2 +O2 → 2H2O
The moles of O2 is determined using the mole ratio of H2:O2
that is from equation above H2:O2 is 2:1
If the moles of H2 is 8 moles therefore the moles of O2
= 8 moles x 1/2 = 4 moles
