Since the half-life is 4.5 billion years, two half-lives would have elapsed after 9 billion years.
<span>If you start with 400 g, half decays during the first half-life, leaving 200 g. </span>
<span>During the second half-life, half of the 200 g decays, leaving 100 g.</span>
They are different by a phase shift of pi/2
The optimum pH of formic acid - formate buffer is 3.75
<h3>What is pH? </h3>
- pH is a measure of how acidic/basic water is. The range goes from 0 - 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base.
- pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water.
What is Buffer ?
A substance or a solution which resists any changes in pH, when acid or alkali is added to it.
pH = pKa + log[base] / [acid]
Considering equimolar concentration of acid and base
pH = 3.75 + log(x)/(x)
pH = 3.75 + log (1)
pH = 3.75 + 0
pH = 3.75
Hence,
The optimum pH of formic acid - formate buffer is 3.75
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Ionic bond is a chemical bond formed by the complete transfer of electrons between two atoms. The atom that loses electrons gains a positive charge (cation) and that which accepts electrons gains a negative charge (anion). Now, electronegativity is a parameter that measures the tendency of an atom to accept electrons. In the context of ionic bonding, two elements which show a significant difference in their electronegativity values form ionic bonds.
In the given examples, the difference in electronegativity is greatest between K and Br i.e. 0.8 and 2.8 respectively with a difference of 2.0. This also makes sense since K and Br are on the extreme ends of the periodic table. Hence, potassium with a valence electron configuration of 4s1 will lose its s electron to Br (4s24p6) and form an ionic molecule K⁺Br⁻
Ans E) potassium and bromine
Answer:
Some serious diseases like anthrax is also caused in animals by the microbes. Microbes also cause diseases of plants like blights in potatoes, sugarcanes, oranges etc. They also reduce the yield. Microbes grow on food products and render them unfit for consumption.
Explanation:
