1) Write the balaced chemical equation:
H2 + 2O2 → 2H2O
2) Infere the molar ratios:
1 mol H2 : 2 mol of water
3) Make the calculus as the direct proportion relation:
[2 mol H2O] / [1 mol H2] * 7 mol H2 = 14 mol H2
As you see you produce the double number of moles of H2O than number of moles of H2 used.
Answer: 14 moles
<u>Answer:</u> The magnitude rating for an earthquake causing an amplitude 10,000,000 times
is 7.
<u>Explanation:</u>
Richter scale is defined as the scale which expresses the magnitude of earthquake on the basis of the seismograph oscillations.
The equation used to measure the magnitude of an earthquake on Richter scale is:

where
I = amplitude registered on seismograph 100 km away from seismic center = 
= small amplitude
Putting values in above equation, we get:

Hence, the magnitude rating for an earthquake causing an amplitude 10,000,000 times
is 7.
The cell membrane acts as a semi-permeable barrier in plants. In other words, is in charge or control of what comes in and out of the cell.
Answer: 
Explanation: 1 gram is equal to 1000 Milligrams so

Since you go straight across its just multiplication so 0.00200x1000=200mg
To answer it in scientific notation it should just be
mg
1. mol ratio of Al(NO₃)₃ : Na₂CO₃ = 2 : 3
2. Na₂CO₃ as a limiting reactant
<h3>Further explanation</h3>
Given
Reaction
2 Al(NO₃)₃ + 3 Na₂CO₃ → Al₂(CO₃)₃ + 6 NaNO₃
Required
mol ratio
Limiting reactant
Solution
The reaction coefficient in the chemical equation shows the mole ratio of the components of the compound involved in the reaction (reactants and products)
1. From the equation mol ratio of Al(NO₃)₃ : Na₂CO₃ = 2 : 3
2. mol : coefficient of Al(NO₃)₃ : Na₂CO₃ = 2 mole/2 : 2 mole/3 = 1 : 0.67
Na₂CO₃ as a limiting reactant (smaller)