The energy change if 84.0 g of CaO react with excess water is 98KJ of heat is released.
calculation
heat = number of moles x delta H
delta H = - 65.2 Kj/mol
first find the number of moles of CaO reacted
moles = mass/molar mass
the molar mass of CaO = 40 + 16= 56 g/mol
mass = 84 g
moles therefore = 84 g/56 g/mol =1.5 moles
Heat is therefore = 1.5 moles x -65.2 = - 97.8 Kj = -98 Kj
since sign is negative the energy is released
A metal ion is a type of atom compound that has an electric<span> charge. </span>Such<span> atoms willingly lose electrons in order to build positive ions called cations.</span>
Answer: The answer is A
Explanation: No because it’s is a mixture because physical methods were used to separate its particals
<span> They </span>do<span> not </span>respond to stimuli<span>, they </span>do<span> not grow, they </span>do<span> not </span>do<span> any of the things we normally associate with life.
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The process through which Polonium is most likely to become stable is: B. alpha decay.
An unstable element refers to a chemical element that lose particles because its nucleus contain an excess of internal energy (neutron or proton).
This ultimately implies that, an unstable element is radioactive in nature.
In Science, some examples of an unstable element are:
Polonium is a chemical element with a large, unstable nucleus.
Basically, the most stable isotope of Polonium is Polonium-209, which typically undergoes an alpha decay to form lead-205 and the emission of an alpha particle.
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In conclusion, we can deduce from the above chemical equation that Polonium is most likely to become stable through an alpha decay.
Read more: brainly.com/question/18214726