To minimize the sharp pH shift that occurs when a strong acid is added to a solution, IT IS PRACTICAL TO ADD A WEAK BASE.
When a strong acid is added to a solution, it usually brings about a sharp change in the pH of the concerned solution. To avoid this, one can add a weak base to the solution first. The weak base will serves as a buffer for the strong acid and prevents the solution from experiencing sharp pH variations.
I'm preatty sure it is in the periodic table xxx
<h2>Answer:</h2>
The option B is correct option. Which is release of heat and/or light energy .
<h3>Explanation:</h3>
According to the definition of exothermic reaction :
<em>An exothermic reaction is a chemical reaction that releases energy by light or heat.</em>
From definition option B (release of heat and/or light energy) indicates that an exothermic reaction has taken place.
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Answer:A) It was developed from past observations- true
It is subject to experimentation and revision.- false
It explains why mass is conserved- false
It predicts future observations-true
Explanation:
Before a hypothesis is proclaimed to be a law in science, numerous observation must have confirmed its validity and rigorous experimentation under carefully controlled conditions usually precedes the acceptance of a hypothesis as a law. The law of conservation of mass was developed from numerous past observation that proved its validity.
We determine the Coulombic force using the Coulomb's Law:
F = kQ₁Q₂/d²
where
k is equal to 9×10⁹ N·m²/C²
Q₁ and Q₂ are the charges of the two particles
d is the distance between them
For this problem, Q₁ = +2(0.16×10⁻¹⁸ C) and Q₂ = -2(0.16×10⁻¹⁸ C), because a single electron or proton has a charge of 0.16×10⁻¹⁸ C. The distance between the two ions is the sum of their radii.
d = radius of Ca²⁺ + radius of O²⁻
d = 0.106×10⁻⁹ m + 0.132×10⁻⁹ m
d = 0.238×10⁻⁹ m
F = (9×10⁹ N·m²/C²)(+2(0.16×10⁻¹⁸ C))(-2(0.16×10⁻¹⁸ C))/(0.238×10⁻⁹ m)²
F = 1.017×10¹¹ N
