Equal to 50
law of reflection: angle of incidence equals angle of reflection
Answer:
b) The isolated system stores 80 J of total energy, but it is converted to a different form of energy.
Explanation:
The Law of Conservation of Energy states that in an isolated system the total energy always remains constant. In our context this means that the box's energy cannot disappear from the isolated system of the box, slide, and the earth. Abiding the Law of Conservation of Energy, as the box slides down the friction-less table, its gravitational potential energy is converted into its kinetic energy.
Thus, in accord with the Law of Conservation of Energy, the energy of the system can neither decrease or increase, but is converted from one from to another. This rules of choices A, B, and C, leaving only choice B as correct.
We will use the formula:
Q = ml
where Q is the heat, m is the mass of substance, and l is the latent heat of vaporization of the substance.
Q = 0.2 x 2.26 x 10³
Q = 452 kJ
Answer:
2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂
2Na + MgCl₂ → 2NaCl + Mg
Explanation:
A balanced chemical equation is a chemical equation that have an equal number of elements of each type on both sides of the equation
Among the given chemical reactions, we have;
2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂
In the above reaction;
The number of phosphorus, P, on either side of the equation = 2
The number of bromine atoms, Br, on either side of the equation = 6
The number of chlorine atoms, Cl, on either side of the equation = 6
Therefore, the number of elements in the reactant side and products side of the reaction are equal and the reaction is balanced
The second balanced chemical reaction is 2Na + MgCl₂ → 2NaCl + Mg
In the above reaction, there are two sodium atoms, Na, one magnesium atom and two chlorine atoms on both sides of the reaction, therefore, the reaction is balanced
