Answer:
use coefficients and subscripts to determine how many atoms are in a compound. If there is no subscript or coefficient, assume it is 1. If there is a coefficient, multiply it with the subscripts. For counting cations and anions, determine first which is the anion and cation (anion = nonmetal, cation = metal), then count the number of that ion.
Example:
NaCl
one atom of Na, one atom of Cl. Since Na is a metal, it is a cation. Cl is a nonmetal, so it is an anion.
2CaCl2
2 atoms of Ca, 4 atoms of Cl. There are 2 cations, since Na is a metal, and 4 anions since Cl is a nonmetal
Hi, you've asked an incomplete question. However, I assumed you are referring to the article found on the Scientific American website.
Explanation:
<em>Remember,</em> according to that article we are told that scientists notice that these insects have a long nymphal (immature form before becoming adults) stage, one that can last up to 13 to 17 years on the ground before they leave the ground looking for mating partners.
Because it is only after mating occurs at this point that their eggs are laid, that is why scientists believe that cicadas only reproduce every 13 or 17 years.
Hey there! :D
This is a true statement. Gamma radiation comes from electromagnetic energy from radioactive decay. This decay has the shortest electromagnetic wave lengths and therefore has the highest photon energy. It is extremely dangerous. Radiation in general is something to be cautious of!
I hope this helps!
~kaikers
Given molecule Lithium iodide (LiI)
Heat of hydration = -793 kj/mol
Lattice energy = -730 kJ/mol
Heat of hydration = Heat of solution - Lattice energy
Heat of solution = Hydration + Lattice = -793 + (- 730) = -1523 kJ/mol
Now,
Mass of LiI = 15.0 g
molar mass of LiI = 134 g/mol
# moles of LiI = 15/134 = 0.112 moles
Heat of solution for 1 mole of LiI = -1523 KJ
Therefore, for 0.112 moles of LiI the corresponding heat is
= 0.112 *(-1532) = 171.6 kJ
