Answer:
A Neutron and a Hydrogen Atom
Explanation:
Hydrogen atom having an atomic mass of 1.008 amu consists of one proton and one electron. Hence, the +ve and -ve charges cancels out and makes the hydrogen atom a neutral specie.
Also, we know that neutron is neutral sub particle while, proton and electron are positively and negatively charged respectively. Therefore, a neutral neutron having no charge becomes equal to hydrogen atom having zero charge due to cancellation of both +ve and -ve charges.
Answer:
ice
Explanation:
uhh concrete has rougher surface
Gravity is<span> a very important force. Every object in space exerts a </span>gravitational<span> pull on every other, and so </span>gravity influences<span> the paths taken by everything traveling through space. It </span>is<span> the glue that holds together entire galaxies. It keeps </span>planets<span> in orbit.
Hope this helps.</span>
1) A. the have different protons.
The number of protons is the atomic number and this is how the products are ordered in the periodic table. Every element has different atomic number.
2) A. 8 p, 8 e and 8 n
The atomic number of O is 8, which means it has 8 protons. The number of protons must equal the number of electrons.
3) C. atoms bond with one another in a molecule.
That is what a molecule is: a group ot atoms bonded.
4) D. the bond results from the attractive forces of two opposite charges.
Ionic bonds are formed between ions, a positive ion (cation) and a negative ion (anion).
5) A. the physical and chemical properties of HCl are different from those of H2 and Cl2
You can check physical properties (density for example) and chemical properties (how they react with other elements) in some tables o textbooks.
Answer:
the standard enthalpy of formation of this isomer of C₈H₁₈ (g) = -375 kj/mol
Explanation:
The given combustion reaction
C₈H₁₈ + 25/2 O₂ → 8 CO₂ + 9 H₂O ............................(1)
Heat of reaction or enthalpy of combustion = -5099.5 kj/mol
from equation (1)
ΔH⁰reaction = (Enthalpy of formation of products - Enthalpy of formation of reactants)
Or, - 5099.5 = [8 x ΔH⁰f(CO₂) +9 x ΔH⁰f(H₂O)] - [ΔH⁰f(C₈H₁₈) + ΔH⁰f(O₂)].................................(2)
Given ΔH⁰f(CO₂) = - 393.5 kj/mol & ΔH⁰f(H₂O) = - 285.8 kj/mol and ΔH⁰f(O₂)= 0
Using equation (2)
ΔH⁰f(C₈H₁₈) = -621 kj/mol
