Answer:
E = 4.78×10^−19 J
Explanation:
The chemical equation for the energy of a photon is given by:
E =hν , where h is the Planck constant and ν is the frequency.
E =hν = 6.626×10^−34 Js × 7.21×10^ 14
s−1 = 4.78 × 10^−19 J
Answer:
An ionic bond is formed by the complete transfer of some electrons from one atom to another. The atom losing one or more electrons becomes a cation or a positively charged ion. The atom gaining one or more electrons becomes an anion which is a negatively charged ion.
The molarity of HCl is calculated as below
find the moles of mg used
moles = mass /molar mass
= 2.00g/24 g/mol=0.083 moles
write the reacting equation
Mg(s) +2HCl (aq)= MgCl2(aq) + H2(g)
by use of mole ratio between Mg to HCl which is 1 :2 the moles of HCl is therefore
= 0.083 x2 =0.166 moles
molarity of HCl = moles of HCl/ volume in dm^3
that is 0.166/50 x1000= 3.3 M of HCl
