Electronegativity is the property of the element to attract electrons to its nucleus. The trend of electronegativity in the periodic table is decreasing from right to left and decreasing from top to bottom. hence from the given elements, the element with the highest electronegativity should be A.beryllium
Na₂S(aq) + Cd(NO₃)₂(aq) = CdS(s) + 2NaNO₃(aq)
v=25.00 mL
c=0.0100 mmol/mL
M(Na₂S)=78.046 mg/mmol
n(Na₂S)=n{Cd(NO₃)₂}=cv
m(Na₂S)=M(Na₂S)n(Na₂S)=M(Na₂S)cv
m(Na₂S)=78.046*0.0100*25.00≈19.5 mg
Graduated cylinder
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Thermometer
Nitrous oxide has 2 nitrogen atoms and 1 oxygen atom per molecule