The surface waves are the type of seismic waves that produce
the most severe ground movement. This wave is slow in nature and so produces a rolling
effect similar to a surface wave in a pond. This kind of wave is far more
devastating than the P waves and the S waves. The surface waves have the
capacity to shake a building from side to side until it collapses. This kind of
wave moves in a pattern similar to a circle. It actually originates at a point
and then start moving outwards in a circle.
Answer:
Fe(CN)₂, FeCO₃, Pb(CN)₄, Pb(CO₃)₂
Explanation:
Cations (positively charged ions) can only form ionic bonds with anions (negatively charged ions). However, you can't just simply put one cation and one anion together to form a compound. Each compound needs to been neutral, or have an overall charge of 0. When cations and anions do not have charges that perfectly cancel, you need to modify the amount of each ion in the compound.
1.) Fe(CN)₂
-----> Fe²⁺ and CN⁻
-----> +2 + (-1) + (-1) = 0
2.) FeCO₃
-----> Fe²⁺ and CO₃²⁻
-----> +2 + (-2) = 0
3.) Pb(CN)₄
-----> Pb⁴⁺ and CN⁻
-----> +4 + (-1) + (-1) + (-1) + (-1) = 0
4.) Pb(CO₃)₂
-----> Pb⁴⁺ and CO₃²⁻
-----> +4 +(-2) + (-2) = 0
Answer:
The 2 would be placed in front of the reactant Na and in front of the product NaCl
2Na + Cl2 = 2NaCl
Explanation:
This is because the ratio of elements needs to be balanced on both sides.
On the reactants side, there are 2 Na molecules and 2 Cl molecules
On the products side, there are 2 Na molecules and 2 Cl molecules
So, now the equation is balanced