⁴⁰Ar
N(e)=18
N(p)=18
N(n)=40-18=22
⁴⁰K
N(e)=19
N(p)=19
N9n)=40-19=21
⁴⁰Ca
N(e)=20
N(p)=20
N(n)=40-20=20
The units of density are g/ml. If you find the grams of 1 mol of ethanol (with the molecular weight), you can then divide by the density to get the ml of ethanol.
g*(ml/g)=ml
Answer: A
Explanation: the only way to turn it from blue to yellow is to mix it with an acidic solution.
