OK in the case of hydrazine 14 grams of nitrogen combine with 2 gram of hydrogen and with ammonia 14 grams combine with 3 grams of hydrogen.
Ratio 2:3
The atomic mass or relative isotopic mass refers to the mass of a single particle, and therefore is tied to a certain specific isotope of an element. The dimensionless standard atomic weight instead refers to the AVERAGE of atomic mass values of a typical naturally-occurring mixture of isotopes for a sample of an element.
You can count it by yourself using formula
m = ({first isotopic distribution%}× {first atomic.mass})+ ({second isotopic distribution%}× {second atomic.mass}) / {100}
Exothermic reaction is when the system releases energy to the surrounding, the energy (in the perspective of the system) will have a sign of negative, as the system is transferring energy towards the surrounding.
Endothermic reaction is when the system is absorbing energy from the surrounding, the energy (in the perspective of the system) will have a sign of positive, as energy is transferred to the system.
The answer is: [B]: "ionic salt" .
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Note: There is no "sharing of electrons" among the elements in this compound; so this compound in NOT a "covalent molecule".
However, there is ionic bonding: Cu²⁺ and Cl⁻ ; to form: "CuCl₂" .
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Ionic bond is formed between positive and negative ions.
Positive ion is known as cation (electropositive metal)
Negative ion is known as anion ( electronegative non-metal)
The bond formed between a metal (positive ion) and non-metal (negative ions) is known as Ionic bond.
Ionic form is formed when one or more electrons from the valence shell of an atom (electropositive metal ) are completely transferred to the valence shell of another atom (electronegative non-metal). Ionic bonding is the complete transfer of valence electron(s) between oppositely charged atoms.
For example: Bond between NaCl(sodium chloride) is an ionic bond in which Na (sodium ) is positive ion(metal) which have +1 charge and Cl (chlorine) is negative ion(non-metal) which have -1 charge and the bond formed between Na+ and Cl- is ionic bond.
