Answer:
NaI
Explanation:
In I₂, HI and IBr, both atoms are nonmetals and they form covalent bonds in which electrons are shared.
In NaI, Na is a metal and I a nonmetal, so they form an ionic bond, where Na loses an electron to form Na⁺ and I gains an electron to form I⁻. Anions and cations are attracted to each other through electrostatic forces.
Since ionic bonds are stronger than covalent bonds, more energy is required to break them in the melting process, thus having higher melting points.
All in all, NaI is the one with the highest melting point.
Answer:
Positron emission
Explanation:
Positron emission involves the conversion of a proton to a neutron. This process increases the mass number of the daughter nucleus by 1 while its atomic number remains the same. The new neutron increases the number of neutrons present in the daughter nucleus hence the process increases the N/P ratio.
A positron is usually ejected in the process together with an anti-neutrino to balance the spins.
Answer:
Millimeters
Explanation:
A kilogram is for weight, Milliliters is volume, Kilometers is length but too big for a shoe, so Millimeters is the answer by elimination.
Answer : The number of electrons in an atom is, 2 electrons
Explanation :
As we know that there are four quantum numbers which are principle quantum number, azimuthal quantum number, magnetic quantum number and spin magnetic quantum number.
The Principle quantum number, n = 3. That means the electron present in the third energy level.
The Azimuthal quantum number, l = 2. That means the electron present in the d sub-shell.
The magnetic quantum number, 
. That means it shows the 2 electrons present in one of the five 3d orbitals.
Hence, the number of electrons in an atom is, 2 electrons
