it states that the atom is neutral, meaning the number of electrons and protons are the same. so if there are 13 electrons, there are 13 protons. And the mass number is neutrons plus protons. So 13+15 is 28
Answer: To melt 500 g of ice, 4000 joule of heat is required.
Explanation:
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Cl⁻ + H₂O(g) = HCl(g) + OH⁻
w - it is percent chloride ions in solid sea salt (as a rule 55%)
m - it is the mass of sea salt
m(Cl⁻)=mw/100
m(Cl⁻)/M(Cl)=V(HCl)/V₀
mw/{100M(Cl)}=V(HCl)/V₀
m=100M(Cl)V(HCl)/{wV₀} (<span>the mass of solid sea salt)</span>
V₀=22.4 L/mol
M(Cl)=35.45 g/mol
for example:
V(HCl)= 1.0 L
w=55%
m=100×35.45×1.0/{55×22.4}=2.88 g