Answer:
Ozon prevents us from UV rays of the sun. Ozone hole means that UV rays are entering the Earth. This results in cancer.
Explanation:
Chlorofluorocarbons are causing this
Answer:
covalent
Explanation:
covalent compounds contain non metals. All of the elements in Octocrylene are non metals
Answer is: nickel (Ni) is the most active metal.
Chemical reaction 1: Pb(NO₃)₂(aq) + Ni(s) → Ni(NO₃)₂(aq) + Pb(s).
Chemical reaction 2: Pb(NO₃)₂(aq) + Ag(s) → no reaction.
Chemical reaction 3: Cu(NO₃)₂(aq)) + Ni(s) → Ni(NO₃)₂(aq) + Cu(s).
From chemical reactions 1 and 3, we can conclude that nickel is more reactive than lead (Pb) and copper (Cu), because lead is more reactive than silver (Ag), chemical reaction 2, nickel is also more reactive than silver.
In chemical reaction 2, no reaction occurs because silver is less reactive than lead. Lead is higher in activity series of metals and can not be reduced.
Nickel is higher in activity series of metals than lead, copper and silver.
The activity series is a series of metals from highest to lowest reactivity. Metal higher in the reactivity series will displace another.
