Enthalpy is the change in energy. A cold pack will react endothermically and enthalpy will be positive and a heat pack will have negative enthalpy. You cannot determine which has more change in enthalpy unless you measure the temperature change. Eg. a heat pack went from 25c to 35c will have greater change in enthalpy then a cold pack going from 25 to 20c because the net temperature difference is greater
A two in both of the blanks will balence the equation. It will look like so:
2PbS(s) + 2O2(g) --> 2PbO(s) +2SO2(g)
the cell structure represented by x is the nucleus
Answer:
18 * 10^19 atoms
Explanation:
We must first convert 57.8 mg to grams.
If 1000 mg = 1g
57.8 mg = 57.8/1000 = 57.8 * 10^-3 g
Now;
If 1 gold atom has a mass of 3.27X10^-22 grams
x gold atoms have a mass of 57.8 * 10^-3 g
x = 57.8 * 10^-3 g/3.27X10^-22 g
x = 18 * 10^19 atoms
Explanation:
White precipitate of silver chloride get dissolves in excess ammonia to formation of complex between silver ions, chloride ions and ammonia molecules.
The chemical reaction is given as:
![AgCl(s)+2NH_3(aq)\rightarrow Ag[(NH_3)_2]^+Cl^-(aq)](https://tex.z-dn.net/?f=AgCl%28s%29%2B2NH_3%28aq%29%5Crightarrow%20Ag%5B%28NH_3%29_2%5D%5E%2BCl%5E-%28aq%29)
When 1 mole of silver chloride is added to 2 mole of an aqueous ammonia it form coordination complex of diaaminesilver(I) chloride.
