Answer:
All of the given statements are true.
Explanation:
All the elements are heavier than Bismuth (Bi) are radioactive.
The time for half of the original sample to spontaneous decay is called half life (
)
All radioactive elements are spontaneously decaying towards formation of a stable element.
Radioactive elements undergo decay in order to attain stability.
Radioactivity is a natural part of our environment. The earth also contains several primordial long-lived radioisotopes that have survived to the present in significant amounts.
Hence, all the given statements are true.
Answer:
Ion-ion force between Na+ and Cl− ions
London dispersion force between two hexane molecules
Explanation:
"Ion-dipole force between Na+ ions and a hexane molecule
" does not exist since hexane has only non-polar bonds and therefore no dipole.
"Ion-ion force between Na+ and Cl− ions
" exists since both are ions.
"Dipole-dipole force between two hexane molecules
" does not exist since hexane molecules do not have a dipole.
"Hydrogen bonding between Na+ ions and a hexane molecule
" does not exist since the hydrogen in the hydrogen bond must be bonded directly to an electronegative atom, which hexane does not have since it is a hydrocarbon.
"London dispersion force between two hexane molecules" exist since hexane is a molecular compound.
Reduction <span>always results in a lowering of the oxidation number. The reaction of the system above is written as:
</span><span>Cu2+(aq) + Fe(s) --> Cu(s) + Fe2+(aq)
</span>
From the reaction, we see that copper goes from the +2 to a neutral charge. Lowering of the oxidation number happens so this is the element that is being reduced.
Answer:
A continent is a large distinct landmass.
There are seven continents on Earth.
Continents cover two-thirds of Earth’s surface.
Explanation:
