The primary difference between a hypothesis and a theory is that a hypothesis is falsifiable but a theory has been proven to be correct. An hypothesis is a proposed explanation put forward on the basis of limited evidence as a commencement point for further investigation, at the end of the investigation the theory may not be accepted if it failed to meet some criteria. A theory is a proven system of ideas used to explain a particular phenomenon.
Answer:
1.93 mol Ca
Explanation:
Use Calcium's molar mass to convert g of Ca into mol of Ca.
It glow, so light energy go out of the system, exotermic
I think the answer is reversible. Reversible reaction is a kind of reaction which can react in both direction at the same time. And when the both side reactions get the same speed, the reaction is at a equilibrium state.
Let MM(x) be the molar mass of x.
MM(Pb) : MM(PbO)
=207.21 : 223.20 = 451.4 g : x g
cross multiply and solve for x
x=223.2/207.21*451.4
= 486.23 g
Percentage yield = 365.0/486.23= 0.75067 = 75.07% (rounded to 4 sign. fig.)