Answer:
The heat of reaction when hydrogen and oxygen combine to form water is :
<u>C. 571.6 kJ</u>
Explanation:
Enthalpy Change = The enthalpy change for the formation of 1 mole of the substance from their standard state is called the enthalpy of formation.
This is intensive quantity as it is fixed for 1 mole .
Intensive properties = Those properties which are independent on the amount of the substance are intensive properties.
The value of these quantities does not get halve if you divide the substance into two equal parts. example , density, refractive index.
However , the enthalpy of reaction is extensive. Because on increasing the amount the value of the enthalpy also get doubles
Hence for this reaction :

Its value is -285.8 kJ for 1 mole
And here two moles are present . so the value of molar enthalpy is:
-285.8 x 2 = -571.6 kJ
The part of an atom that is actively exchanged or shared in a chemical bond is ELECTRON.
An atom is made up of three sub particles, which are electron, proton and neutron. The proton and the neutron are located in the nucleus of the atom and they make up the major mass of the atom. The electron is located outside of the nucleus and it orbit around the nucleus; it has negligible mass. The electron is negatively charged and because it is located outside of the nucleus, it is the one that is always involved in chemical reactions. There are different types of chemical bonds in chemical compounds and it is electrons that are normally used to form these bonds. During bond formation, electrons can either be donated or shared.
The 28 is the sum of the protons and neutrons in the element silicon.
ALL silicon atoms have 14 protons in the nucleus, so we can turn this into an equation:
#protons + #neutrons = 28
14 + #neutrons = 28
#neutrons = 14
#protons = 14
What is [H+] given that the measured cell potential is -0.464 V and the anode reduction ... What half-reaction occurs at the cathode during the electrolysis of molten ... PbO2(s) + 4H+(aq) + SO42-(aq) + 2e- → PbSO4(s) + 2H2O(l); E° = 1.69 V .... For the cell Cu(s)|Cu2+||Ag+|Ag(s), the standard cell potential is 0.46 V. A cell ... hopw this helps
The element aluminum forms a cation with the charge of +3. The symbol for this ion is Al³⁺, and the name is aluminum ion. The number of electrons in this ion 10.
<h3>What are ions?</h3>
Ions are formed when an atom gains or loses electrons.
Metals form positive ions by a loss of electrons whereas non-metals form negative ions by gaining electrons.
The aluminum ion is formed when aluminum loses three electrons to form Al³⁺ ion which has 10 electrons.
in conclusion, ions are formed by a gain or loss of electrons.
Learn more about ions at: brainly.com/question/490569
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