Na2C03 is formed through the reaction of
NaOH and H2CO3 namely sodium hydroxide and carbonic acid
NaOH -> strong base
H2CO3-> weak acid
1) Molecular formula of ammonium sulfide
(NH4)2 S
2) That means that there are 2*4 = 8 atoms of hydrogen in each molecule of ammoium sulfide, so in 5.20 mol of molecules will be 8 * 5.20 mol = 41.6 moles of atoms of hydrogen
3) To pass to number of atoms multiply by Avogadro's number: 6.022 * 10^23
41.6 moles * 6.022 * 10^23 atoms / mol = 250.5 * 10^23 = 2.50 * 10^25 atoms
Answer: 2.50 * 10^25
Option B, Bronze is made of the metals copper and tin.
Alloys are essentially materials that consist of two or more metal elements.
-T.B.
Explanation:
Over 99.9% percent of an atom's mass resides in the nucleus. The protons and neutrons in the center of the atom are about 2000 times heavier than the electrons orbiting around it.
Because the electrons are so light by comparison,they represent only a tiny fraction of a percent of the atom's total weight.
Hope this answer helps you!
