People firstly believe that the planets move in a circular orbit until Newton came up with his hypothesis by inventing calculus so that we could understood and calculated planetary orbits and their accuracy.
<u>Explanation:</u>
- Everyone assumed the planets were perfect circles until Newton came up with an idea. Slowly people would make maps of the orbits that added circles on circles, and they could never really explain about the movement of the planet. They simply say that planets move on circles but they lacked the math to explain or prove it. Then Newton came up with an idea of inventing calculus so that we could understood and calculated planetary orbits and their accuracy.
- Firstly people used their observations and say that the orbits looked like circles, then they developed their models and did the math, and proposed their hypothesizes which were wrong, until Newton came along and tried to match a model that used elliptical orbits and invented the math that allowed him to make predictions with it. His model worked for most planets.
- However he could not explain about the planet Mercury for instance since it was a very strange orbit. Then after the Einstein's theory of General Relativity he could also explain very deeply about it.
- Scientists and Astronomers made hypothesizes that there was another planet orbiting too close to the sun to see with telescopes, called Vulcan, that explained mercury's orbit before Einstein's theory. Then long after we had telescopes which was good enough to see if there was a planet orbiting closer to the sun than mercury.
Answer:
It is greater than -600kJ/mol and the amount of energy required to break bonds is greater than the amount of energy released in forming bonds.
Explanation:
In an endothermic reaction, the reaction requires a determined amount of energy to occurs.
The reaction of the problem has H = -600kJ/mol. The reaction is endothermic and the energy that the reaction needs is absorbed by the reactants. That means, the energy of products:
Is greater than -600kJ/mol and the amount of energy required to break bonds is greater than the amount of energy released in forming bonds.
Density is defined as mass per unit volume.

the mass of 1 mL of CO₂ is - 0.0019 g
3.5 L = 3500 mL
then the mass of 3500 mL of CO₂ is - 0.0019 g/mL x 3500 mL = 6.65 g
mass of 3.5 L of CO₂ is 6.65 g
Answer: The balanced equation is 4,3,2,
Answer: Balanced equation = 4Fe + 3O2 => 2Fe2O3.
Explanation: