Answer: Atoms that make up reactants rearrange into new products
Explanation:
A chemical reaction is the process of breaking down the chemical bonds of the reacting substances which are commonly called as reactants and making new bonds to form new substances commonly called as products.
The products will contain the same atoms as there are in the reactants but the bonds will rearrange to form different substances.
Every chemical reaction is accompanied with absorption or release of energy.
Radioactivity in our world <span>b. is as old as the universe.
</span><span>Radioactive atom spontaneously emits energetic particles or waves, while decays on lighter nuclei (atoms with smaller atomic mass). Radioactivity is used to calculate how old is Earth and living things, for that purpose isotope of carbon is used.</span>
Zinc Oxide is the IUPAC name for ZnO
Answer:
kb = 2,0x10⁻⁵
Explanation:
The ka for HCN is:
HCN ⇄ H⁺ + CN⁻; ka = 4,9x10⁻¹⁰ <em>(1)</em>
The inverse reaction has an equilibrium constant of:
H⁺ + CN⁻ ⇄ HCN k = 1/4,9x10⁻¹⁰ = 2,0x10⁹ <em>(2)</em>
As the equilibrium of the water is:
H₂O ⇄ H⁺ + OH⁻; kw = 1x10⁻¹⁴ <em>(3)</em>
The sum of (2) + (3) gives:
H₂O + CN⁻ ⇄ HCN + OH⁻; kb = kw×k = 1x10⁻¹⁴×2,0x10⁹ =
2,0x10⁻⁶; <em>kb = 2,0x10⁻⁵</em>
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<em>-In fact, the general formula to convert from ka to kb is:</em>
<em>kb = kw / ka-</em>
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I hope it helps!
B. Earth’s tilt
Earth’s tilt exposes different parts of the earth to varying degrees of sunlight throughout the year, causing seasons.