To find the number of neutrons, subtract the number of protons from the mass number. number of neutrons=40−19=21.
1. Physical matter
2. Chemical matter
3. Physical matter
4. Physical matter
5. Chemical matter
6. Physical matter.
<span>The Avogadro constant, named after the scientist Amedeo Avogadro, is the number of constituent particles, usually atoms or molecules, that are contained in the amount of substance given by one mole. The answer, in this case, would be 0.0004999...*10^23 = (10^19)*(4.999... [any finite number of 9s]).</span>
Assume it is 1 litre and weighs 1kg.
2 percent of 1 kg is 20g.
20g divided by molar mass of NaOH.
20g divide by 40 = 0.5 mole
0.5 mole in a litre would be 0.5M
That is the answer: 0.5M
