Answer:
C
Explanation:
The chemical energy stored in the match changed to thermal energy and light energy.
Answer:
33.33 h
Explanation:
You know that
1 h = 60 min
If you divide both sides by 60 min, you get the conversion factor: 1 h/60 min = 1.
If you divide both sides by 1 h, you get the conversion factor: 1 = 60 min/1 h.
Both are conversion factors because they both equal one and multiplying a measurement by one does not change its value.
You choose the conversion factor that gives you the correct dimensions for your answer. It must have the correct dimensions on top (in the numerator),
Thus, to convert 2000 min to hours, you use the conversion factor with “h” on the top.

Answer:
0.683 moles of the gas are required
Explanation:
Avogadro's law relates the moles of a gas with its volume. The volume of a gas is directely proportional to its moles when temperature and pressure of the gas remains constant. The law is:
V₁n₂ = V₂n₁
<em>Where V is volume and n are moles of 1, initial state and 2, final state of the gas.</em>
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Computing the values of the problem:
1.50Ln₂ = 5L*0.205mol
n₂ = 0.683 moles of the gas are required
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When the solute can no longer dissolve in the solution the solvent becomes SATURATED. When no more solute can dissolve and if you look at the bottom of the beaker, test tube, pan, or glass of cold tea you can see the solute permeating out as little particles .
The answer is 2. this makes the equation 2Cu + S8 —> Cu2S