Answer:
Noble Gases are very stable because...
1) Noble Gases have a full octet
2) Low chemical reactivity
Explanation:
This means that is has 8 valence electrons so it won't need any more, so it is less likely to react with other substances.
Answer: A. Is decomposition
B. Is synthesis where Na combines with Cl to form NaCl
C. Is single displacement or replacement. Mg displaces Cu.
Explanation:
Answer : The correct option is, (2) Cr (Chromium)
Explanation :
The reactivity series of metal are arranged of the reactivity from the highest to the lowest. Reactivity series is used to determine the products of the single displacement reactions. In the single displacement reaction, the most reactive metal displaces the least reactive metal.
From the given reactivity series we conclude that there are two metal (Mg and Cr) are more reactive metal than the Ni and there are two metal (Pb and Cr) are less reactive metal than the Zn. So, the Cr (Chromium) is the metal which is more active than Ni and less active than Zn.
Hence, the correct option is, (2) Cr
(4) total number of valence electrons, because they exist in the same group.
As the gas is heated, the particles will begin to move faster. Likewise if you start to cool a gas, the particles will move slower. Because the gas remains at a constant pressure and volume, the particles cannot spread out so they simply move around the container even faster.
Hope this helps :)