Liquid petrol does not ignite spontaneously when exposed to the air because there is not enough molecules that contains energy to reach the activation energy. As a result, the reaction cannot proceed and a supply of energy should be added for the reaction to occur.
The answer is C. Light because light is a form of energy
Answer: See description
Explanation:
Kepler's laws have three principal points:
1. planets orbit the sun in elliptical paths
2. the orbial period is related to the orbital distance by 
where T is the orbital period and d is the orbital distance, T is in years and d is measured in units of the earth sun distance.
3. planets closer to the sun move faster than planets far away from it.
Newton:
Newton discovered that there is a consequence to the gravity exerted by objects: mass, the heavier the planet, the more gravitational force it posseses ( thats why we orbit the sun)
with the gravitational force
newton discovered the inverse-quadratic relationship between the distance of the planets and the acceleration exerted by the force one could exert on another.
Kepler's laws were mostly based on observed evidence with quantitative relationships between the mentioned variables. Newton's laws are based on calculus and symbolic equations. While Kepler's mode is basic, Newton took another step in and build a more general model for gravity (which was improved by general relativity later). In a nutshell Newton proved the scientific causes for Kepler's laws...
There's a slight error in your equation. I think you were trying to present it like this:
2C8H18 + 25O2 -> 16CO2 + 18H2O
Mole Ratio
O2 : H20
25 : 18
? moles : 18 moles
(18/18)×25 : 18 moles
25 moles : 18 moles
Final answer would be 25 moles of O2. :)
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