Answer:
1,2,5
Explanation:
Hydrogen can't really be classified into any group in the periodic table because it doesn't have properties that match that of any group exactly. However it exhibits a property of group 1A (formation of a univalent positive ion) and that of group 7A (formation if a univalent negative ion). It contains only one electron, hence this outermost electron is not shielded at all from the nucleus.
This is the only option that correctly describe characterisitics of noble gases.
All noble gases have a unique atomic fingerprint.
All noble gases have valence shells with 8 electrons but Heilum has only 2 valence electrons.
And all noble gases do not easily react with other elements as they have their outermost shell completly filled so they are highly stable.
All noble gases emits different colored light when electrified.
Answer:
C2H6 + 2 Cl2 = C2H4Cl2 + 2 HCl
Explanation:
This is thermodynamics. When you increase the temperature of an object, the particles gain on kinethic energy ergo the move faster. When you decrease it, they slow down.