Answer:
H+ and NO3- ions
Explanation:
The Pb²+ ions react with the SO4²‐ ions to form a solid precipitate, i.e. they bond together and undergo a phase change;
On the contrary, the H+ and NO3- ions are aqueous ions before the reaction and the same after the reaction, i.e. they don't change;
Hence, the H+ and NO3- ions are spectator ions
The way to do this type of question is to consider what changes and what doesn't, look at phase changes and oxidation state changes
The correct option is B. To get the number of atom for each compound, each element in the compound will be counted as an atom. For instance, for Fe[ClO4]2, there are 1 atom of Fe, 2 atoms of Cl, and 8 atoms of O, making a total of 11 atoms [1 + 2 + 8= 11]. The other options have less than 11 atoms.
Answer:
to measure seismic waves
Explanation:
it's used during earthquakes to tell how big on the richter scale the earthquake was
I believe the answer is "hard water"
