Lucite ,also called plexiglas,British Perspex,trademark name of polymethyl methacrylate.a synthetic organic compound of high molecular weight made by combination of many simple molecules of the ester methyl methacrylate(monomer)into long chains (polymer) the process (polymerization) may be effected by light or etc.
Answer: Synthesis/ Combination
reaction
4 Al + 3S2 => 2 Al2S3
Explanation: The equation is now balanced the amount of each individual atom in both the reactant and product sides are equal.
Answer:
Choice A: Approximately
joules.
Explanation:
Apply the famous mass-energy equivalence equation to find the energy that correspond to the
kilograms of mass.
,
where
stands for energy,
stands for mass, and
is the speed of light in vacuum.
The speed of light in vacuum is a constant. However, finding the right units for this value can simplify the calculations a lot. What should be the unit of
?
The mass given is in the appropriate SI unit:
Mass is in kilograms.
Thus, proceed with the speed of light in SI units. The SI unit for speed is meters per second. For the speed of light,
.
Apply the mass-energy equivalence:
.
The unit of energy is not in joules. Don't be alerted. Consider the definition of a joule of energy. One joule is the work done on an object when a force of one newton acts on the object in the direction of the force through the distance of one meter. (English Wikipedia.)
.
However, a force of one newton is defined as the force required to accelerated an object with a mass of one kilogram (not gram) at a rate of one meter per second squared. (English Wikipedia.)
.
In other words, the mass defect here is also
.