Answer:
Explanation:
First Question. Answer is: B. They are different.
For examle, balanced chemical reaction of forming water from hydrogen and oxygen:
2H₂ + O₂ → 2H₂O.
During chemical reaction no particles are created or destroyed, the atoms are simply rearranged from the reactants to the products.
Oxygen (element) has boiling point of -183°C and hydrogen has boiling point of -253°C. In this chemical change water (compound) is produced and it has new boiling point, boiling point of water is 100°C.
Answer:
pH = 12.80
[H3O+] = 1.58 * 10^-13 M
[OH-] = 0.063 M
Explanation:
Step 1: Data given
pOH = 1.20
Temperature = 25.0 °C
Step 2: Calulate pH
pH + pOH = 14
pH = 14 - pOH
pH = 14 - 1.20 = 12.80
Step 3: Calculate hydronium ion concentration
pH = -log[H+] = -log[H3O+]
12.80 = -log[H3O+]
10^-12.80 = [H3O+] = 1.58 * 10^-13 M
Step 4: Calculate the hydroxide ion concentration
pOH = 1.20 = -log [OH-]
10^-1.20 = [OH-] = 0.063M
Step 5: Control [H3O+] and [OH-]
[H3O+]*[OH-] = 1* 10^-14
1.58 *10^-13 * 0.063 = 1* 10^-14
Unstable isotopes occur when the strong force is unable to overcome the <span> <span>electrostatic force.</span></span><span>
There are no stable isotopes in the elements at the upper end of the periodic table, which clearly demonstrates the limit of the ability of the nuclear binding energy or the residual strong force, to overcome the electrostatic repulsion of all those protons in the nucleus.
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