Answer:
They all have the same number of protons but different numbers of neutrons.
Explanation:
Elements will always have the same number of protons no matter the isotopes. Isotopes only change the number of neutrons. Silicon will always have 14 protons. So silicon-28 has 14 protons and 14 neutrons. Silicon-29 has 14 protons and 15 neutrons. Silicon-30 has 14 protons and 16 neutrons.
Answer:
The magnesium will burn until consumed entirely. There is much more oxygen available in the atmosphere than needed to consume the magnesium. Thus the magnesium is the limiting reactant because it determines the amount of product formed.
Explanation:
Mg produces less amount of MgO than O2; therefore Mg is the limiting reagent. O2 produces more amount of MgO than Mg; therefore O2 is the excess reagent.
Everything requires energy to move. If the desk is moving, then it has energy.
Answer:

Explanation:
Hello!
In this case, considering the Gay-Lussac's law which describes the pressure-temperature behavior as a directly proportional relationship by holding the volume as constant, we write:

Whereas solving for the final temperature T2, we get:

Thus, we plug in the given data (temperature in Kelvins) to obtain:

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