No. Of protons = mass no. - no. Of neutrons
No. Of protons = 67 - 37
= 30
No. Of electrons = 28
Zinc will have 30 protons and 28 electrons. So, it will have +2 charge
Symbol - Zn^+2
the reaction is
2NO(g) + 2H2(g) <—> N2(g) + 2H2O (g)
Kc = [N2] [ H2O]^2 / [NO]^2 [ H2]^2
Given
moles of NO = 0.124 therefore [NO] = moles /volume = 0.124 /2 = 0.062
moles of H2 = 0.0240 , therefore [H2] = moles / volume = 0.0240 / 2 = 0.012
moles of N2 = 0.0380 , therefore [N2] = moles / volume = 0.0380 / 2 = 0.019
moles of H2O = 0.0276 , therefore [H2O] = moles / volume = 0.0276 / 2 = 0.0138
Kc = (0.019) ( 0.0138)^2 / (0.062)^2 ( 0.012)^2 = 6.54
According to the calculation, set I is both the most accurate and most precise.
Exactness is a quality or state of being precise. 2a: comparison accuracy sense: the degree of precision with which an action is carried out or a measurement expressed 2b. The novel was fact-checked for historical authenticity. 2a: conformance to truth, to a standard, or to a model: exactness It is impossible to estimate the number of casualties with accuracy. Let's calculate the precision for the fourth set, considering
Δ1 = ∣(8.41−8.56)∣ g=0.15 g
Δ2 = (8.72−8.56) g=0.16 g
Δ3 = ∣(8.55−8.56)∣ g=0.01 g
Therefore: 
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