4.0 % in mass per volume :
4.0 g ---------- 100 mL
1.2 g ---------- ( volume )
Volume = 1.2 x 100 / 4.0
Volume = 120 / 4.0
= 30 mL
hope this helps!
When neutron numbers are changed an ISOTOPE of the element is formed...
the atom becomes an ISOTOPE
Answer:
<em>Oxygen has 8 protons in the nucleus while nitrogen only has 7. A bonding pair will experience more attraction from the oxygen's nucleus than from nitrogen's, and so the electronegativity of oxygen is greater.</em>
C- main sequnce
Regulus A is a binary star consisting of a blue-white main sequence star of spectral type B7V, which is orbited by a star of at least 0.3 solar masses, which is probably a white dwarf. The two stars take approximately 40 days to complete an orbit around their common centre of mass.